Prelim-Histo (2) PDF

Alyssa E. Amper – BMLS10-2C  Haematoxylin and eosin – most common histologic stain. HUMAN HISTOLOGY  HISTOLOGY – is the study of tissues of the body and how these tissues are arranged to...

Alyssa E. Amper – BMLS10-2C  Haematoxylin and eosin – most common histologic stain. HUMAN HISTOLOGY  HISTOLOGY – is the study of tissues of the body and how these tissues are arranged to constitute organs.  From the greek work “histo” which means LIGHT MICROSCOPY either “tissues” or “web”  TISSUES – are made of two interacting  Used to reveal and study tissue features components: cells and extracellular matrix.  Includes conventional bright-field  Tissue classification is based on structure of microscope, fluorescence microscope, cells, composition of noncellular extracellular phase-contrast microscope, differential matrix, and cell function interference, confocal, and polarizing microscope. TISSUE PREPARATION 1. BRIGHT-FIELD MICROSCOPY o Widely-used type of microscopy  Tissue/slices preparation for histological o Stained preparations are examined sections – the most common procedure use by means of ordinary light that in the study of tissues which can be aided by passes through the specimen. a microscope.  Histologic sections – are thin, flat slices of fixed and stained tissues or organs mounted on glass slides. ADDITIONAL:  Dehydration – transferred to a series increasingly concentrated alcohol. 75, 90, and 100%. 2. FLUORESCENCE MICROSCOPY  Clearing – alcohol needs to be removed and o Tissues are usually irradiated by water content when it is thoroughly like ultraviolet light and the emission is saline and toluene. in the visible portion of the  Infiltration – the tissue is placed spectrum.  Embedding – put in a mold put wax to make o The fluorescent substance appears a solid tissue block. Form trankikad? brilliant on a dark background. pyramid  RESULT: TO COME UP STAINED TISSUE MICROTOME: Rotary microtome? 3. PHASE-CONTRAST MICROSCOPY AND 5. POLARIZING MICROSCOPY DIFFERENTIAL INTERFERENCE o Allows the recognition of structures MICROSCOPY made of highly organized molecules o PCM uses a lens system that produces visible images from transparent objects. o PCM is based on the principle that light changes its speed when passing through cellular and extracellular structures with different refractive indices. o DIM produces an image with a more apparent three-dimensional aspect than in routine PCM. o Sinomarski or Hoffsmann 6. ELECTRON MICROSCOPY o Based on the interaction of electrons and tissue components. The wavelength in the electron beam is much shorter than of light, allowing a thousand-fold increase in resolution. 4. CONFOCAL MICROSCOPY o Avoids stray light and achieves 7. TRANSMISSION ELECTRON greater resolution by using a small MICROSCOPY point of high-intensity light provided o Is an imaging system that permits by a laser and a plate with a pinhole resolution around 3um. aperture in front of the image o Allows magnification of up to 400,000 detector. times to be viewed with details. o Greatly improves resolution of the o TEM functions on the principle that object in focus and allows the beam of electrons can be deflected by localization of specimen electromagnetic fields in a manner components with much greater similar to light deflection in glass lenses. precision than with the bright-field microscope. 8. SCANNING ELECTRON MICROSCOPY o Most confocal microscopes include o Permits pseudo-three-dimensional views of a computer-driven mirror system to the surfaces of cells, tissues, and organs. move the point of illumination o The beam does not pass through the across the specially automatically specimen. and rapidly. PLANE OF SECTION OF A ROUND OBJECT  TANGENTIAL – tangential sections do not reveal sufficient detail for correct  MIDLINE (longitudinal and transverse) interpretation of the egg (tissue) size or its contents or their distribution within the internal membrane. PLANES OF SECTION OF A TUBE 1. Longitudinal 2. Tangential 3. Oblique 4. Transverse 5. Transverse (sharp curve in the  PERIPHERAL tube)  LONGITUDINAL – cuts the tube in the midline produces a U-shaped structure.  TRANSVERSE – produce round structures lined by a single layer cells. A transverse section of a straight tube can produce a single image. The double images of the same structure can represent either two tubes running parallel to each other or a single tube that has a curved in the space of  TANGENTIAL the tissue or organ that is sectioned.  TANGENTIAL – produces a solid, multicellular, oval structure that does not resemble a tube.  OBLIQUE – produces an oval structure that includes an oval lumen in the center and multiple cell layers at the periphery.  TRANSVERSE (sharp curve in the tube) – grazes the innermost cell layer and produces two round structures connected by a multiple, solid layer of cells. These sections  MIDLINE (longitudinal and transverse) – of the tube also contain round lumen, these two planes of section reveal the indicating that the plane of section passed correct appearance, size, and distribution of perpendicular to the structure. the internal contents within the egg (tissue).  PERIPHERAL (longitudinal and transverse) – the sections were cut peripheral to the midline, the internal contents of the egg (tissue) are not seen in their correct size or distribution within the egg white. In addition, the size of the egg (tissue) appears smaller. INTERPRETATION OF STRUCTURES PREPARED o Monocyte cytoplasm stains plae BY DIFFERENT TYPES OF STAINS blue and nucleus stains medium blue  The most prevalent stain that is used for o Neutrophil nuclei stain dark blue. preparation of histology slides is hematoxylin o Eosinophil nuclei stain dark blue and eosin (H&E) stain. and the granules stain bright pink  Hematoxylin and Eosin Stain o Platelets stain light blue o Nuclei stain blue  Cajal’s and Del Rio Hortega’s Methods o Cytoplasm stains pink or red (Silver and Gold Methods) o Collagen fibers stain pink o Myelinated and unmyelinated fibers o Muslces stain pink and neurofibrils stain blue-black  Masson’s Trichrome Stain o Genral background is nearly o Nuclei stain black or blue black colorless o Muscles stain red o Astrocytes stain black o Collagen and mucus stain green or o Depnding on the metod used, the blue end product can stain balck, brown, o Cytoplasm of most cells stains pink or gold.  Periodic Acid-Schiff Reaction (PAS) –  Osmic Acid (Osmium Tetroxide) Stain glycogen o Lipids in general stain black o Glycogen stains deep red or o Lipids in myelin sheath of nerves magenta stain black. o Contents of goblet cells in digestive organs and respiratory epithelia stain magenta red o Basement membranes and brush borders in kidney tubules stain positive, or pink  Verhoeff’s Stain for Elastic Tissue o Elastic fibers jet black o Nuclei stain gray o Remaining structures stain pink  Mallory-Azan Stain o Fibrous connective tissue, mucus, and hyaline cartilage stain deep blue o Erythrocytes stain red-orange o Cytoplasm of liver and kidney stains pink o Nuclei stain red  Wright’s or Giemsa’s Stain o Erythrocytes cytoplasm stain pink o Lymphocyte nuclei stain dark purple-blue with plae blue cytoplasm  TISSUES or move to the opposite cell surface where they fuse with the membrane and release THE CELL AND THE CYTOPLASM their contents outside the cell. PLASMA MEMBRANE (cell membrane or PHAGOCYTOSIS plasmalemma)  Cell eating  forms and important barrier or boundary  Refers to the ingestion or intake of large between the internal and the external particles by the cells, such as bacteria, worn environments out cells, or cellular debris.  Selective permeability  Fusion of the membranous folds encloses the bacterium in an intracellular vacuole CYTOPLASM called a phagosome which then merges with a lysosome for degradation of its  A dense, fluid like medium that contains contents numerous organelles, microtubules, microfilaments, and membrane-bound PHAGOCYTOSIS - results to phagosome secretory granule or ingested material. PINOCYTOSIS – results to pinocytotic vesicles CELL MEMBRANE PERMEABILITY AND MEMBRANE TRANSPORT RECEPTOR-MEDIATED ENDOCYTOSIS SELECTIVE PERMEABILTY  Specific molecules in the extracellular fluid bind to receptors on the cell membrane and  Forms an important barrier between the are then taken into the cell cytoplasm. internal and external environments of the cell which then maintains a constant intracellular environment. ENDOCYTOSIS  Performs the uptake and transfer of molecules and solids across the cell membrane into the cell interior. CELLULAR ORGANELLES EXOCYTOSIS MITOCHONDRIA  The release of material from the cell  Round, oval, or elongated structures whose cytoplasm across the cell membrane. variability and number depend on cell function. It consists of an outer (selective PINOCYTOSIS barrier to molecules) and inner (numerous  Cell drinking folds called cristae) membrane.  The process by which cells ingest small ENDOPLASMIC RETICULUM (ER) molecules of extracellular fluids or liquids.  The resulting pinocytotic vesicles (~80 nm  An extensive network of sacs, vesicles, and in diameter) then pinch off inwardly from the interconnected flat tubules called cisternae. cell surface and either fuse with lysosomes   ROUGH ER – characterized by numerous MICROFILAMENTS flattened, interconnected cisternae, whose cytoplasmic surfaces are covered or studded  shape the cells, and are involved in cell with dark-staining granules called movement and movement of the cytoplasmic ribosomes. organelles. They are distributed throughout  SMOOTH ER – consists primarily of the cells and rare used as anchors at cell anastosoming or connecting tubules. In most junctions. cells, smooth endoplasmic reticulum is INTERMEDIATE FILAMENTS continuous with rough endoplasmic reticulum.  Function vary among cell types and have specific distribution in different cell types. GOLGI APPARATUS 1. Keratin – epithelial cells  composed of a system of membrane-bound, 2. Vimentin – mesenchymal cells smooth, flattened, stacked, and slightly 3. Desmin – smooth and striated muscles curved cisternae. 4. Neurofilament – nerve cells and their processes RIBOSOMES 5. Glial filaments – astrocytic glial cells 6. Lamin – inner layer of the nuclear  Are small, electron-dense granules found in membrane the cytoplasm of the cell; a membrane does not surround ribosomes. They have an MICROTUBULES important role in protein synthesis and are most abundant in the cytoplasm of protein-  Determine cell shape and function in secreting cells. intracellular movement or organelles and secretory granules and form spindles that LYSOSOMES guide the movement of the chromosomes during cell division or mitosis.  They contain a variety of hydrolyzing or digestive enzymes called acid hydrolases. CENTROSOME The main function of lysosomes is the intracellular digestion or phagocytosis of  Microtubule-organizing center. substances taken into the cells. CYTOPLAMIC INCLUSIONS PEROXISOMES  Are temporary structures that accumulate in  Contain several types of oxidases, which are the cytoplasm of certain cells. Lipids, enzymes that oxidize various organic glycogen, crystals, pigment, or byproducts of substances to form hydrogen peroxide, a metabolism are inclusion and represent the highly cytotoxic product. nonliving parts of the cells. CYTOSKELETON NUCLEUS  a network of tiny protein filaments and  The control house of the cell. It also carries tubules that extend throughout the cytoplasm the genes, structures that contain the which serves as the cell’s structural hereditary information of an organism. framework.  Mother board of the cell. NUCLEAR ENVELOPE 6. Lubrication between two surfaces (e.g., mesothelium of pleural cavity)  A double membrane that surrounds the nucleus. NUCLEOLUS MAIN CHARACTERISTICS OF THE FOUR BASIC TYPES OF TISSUES  A dynamic membrane-less structure whose function is ribosomal RNA synthesis and TISSUE CELLS EXTRACELL MAIN ULAR FUNCTIONS ribosome biogenesis. MATRIX Nervous Intertwining None Transmissio NUCLEAR PORE elongated n of nervous processes impulses  The responsible for the entrance and exit of Epithelial Aggregated Small Lining of genetic material towards and inwards. polyhedral amount surface or cells body EPITHELIAL TISSUE cavities, glandular EPITHELIUM secretion Muscle Elongates Moderate Movement  An avascular (having few or no blood contractile amount vessels) tissue, which lacks a direct blood cells supply. Connecti Several Abundant Support and ve types of amount protection  Nutrients are delivered by diffusion from fixed and blood vessels in the neighboring connective wandering tissue. cells  From Greek word epi meaning “upon” and thele meaning “nipple”  Epithelial cell nuclei have a distinctive shape, CLASSIFICATION OF EPITHELIAL TISSUES varying from spherical to elongated or elliptic Based on number of layers of cells:  MOST EPTHELIAL TISSUES ARE RENEWED CONTINUOSLY.  SIMPLE  STRATIFIED BASIC FUNCTIONS: Based on shapes of cells in superficial layer 1. Protection of the body from abrasion and injury (e.g., skin and esophagus)  Squamous epithelium 2. Absorption of material from lumen (e.g.,  Cuboidal epithelium tubules in kidney, small and large  Columnar epithelium intestines)  Transitional epithelium (urothelium) 3. Transportation of material along surface (e.g., cilia-mediated transport in the trachea) 4. Secretion of mucus, hormones, and proteins (e.g., glands) 5. Gas exchange (e.g., alveoli in the lung)  COMMON TYPES OF COVERING EPITHELIA THE SPECIALIZATION OF THE APICAL SURFACE HUMAN BODY (APICAL DOMAIN) NUMBER OF CELL FORM EXAMPLES OF MAIN 1. Cilia – elongated, motile structures that have CELLS LAYERS DISTRIBUTION FUNCTION a greater diameter and length than microvilli. Simple (one Squamous Lining of Facilitates the  Arise from basal bodies layer) vessel movement of  Function: aid in the transport of (endothelium). the viscera Serous lining (mesothelium), material along the surface of of cavities; active transport epithelial cells. pericardium, by pinocytosis 2. Microvilli – smaller than cilia; compose of pleura, (mesothelium actin microfilaments peritoneum and (mesothelium) endothelium),  Anchored to a network structure- secretion of terminal web-which contains actin biologically filaments to stabilize the microvillus active molecules  Function: aid in absorption (mesothelium) 3. Stereocilia – long microvilli; consists of actin microfilaments Covering,  Function: help which absorption Cuboidal Covering the secretion Columnar ovary, thyroid Protection, Lining of lubrication, intense, abdosrption, SPECIALIZATION OF THE LATERAL SURFACE gallbladder secretion (LATERAL DOMAIN) Pseudostrartified Lining of Protection, (layers of cells trachea, secretion; cilia- 1. Zonula occludens (tight junctions) – with nuclei with bronchi, nasal mediated completely surround the apical cell borders different levels; cavity transport of not all cells reach particles to seal the underlying intercellular cleft from surface but all trapped in the outside environments. adhere to basal mucus out of 2. Zonula adherens (adhering junctions) – lamina) the air found just beneath the tight junction, also passages Stratified (two or Squamous Epidermis Protection; forming a bandlike junction surrounding the more layers) keratinized prevents water entire cell and serving to attach adjacent (dry) loss cells. 3. Desmosomes – located beneath the Squamous Mouth, Pretection, nonkeratinized Esophagus secretion; adhering junctions, also assist in cell to cell (moist) prevents water attachment. loss 4. Gap junctions – are communicating junctions, provide a low-resistance channel Cuboidal Sweat galnds, Protection, developing secretion to permit passage of ions and small ovarian molecules between adjacent cells. follicles Transitional Bladder, Protection, ureters, renal distensibility calyces Columnar Conjunctiva Protection SPECIALIZATION OF THE BASAL SURFACE protection is not important; secretes (BASAL DOMAIN) lubrication substances in serosae.  LOCATIONS: lining the posterior surface of 1. Basal Lamina - a sheet of extracellular the cornea; lining blood vessels and material on all epithelial cells in contact with lymphatic vessels (endothelium); lining the subjacent connective tissue at their basal surface of the body cavities (pericardial, surfaces. pleural, peritoneal – mesothelium); and lining  Macromolecular components of the alveoli of the lungs. basal laminae:  Laminin – these are large glycoprotein molecules that self- assemble to form a lace-like sheet immediately below the cells basal poles where they are held in place by the transmembrane integrins.  Type IV collagen – monomers of the type IV collagen contain three polypeptide chains and seld- assemble further to form a felt-like CLINICAL SIGNIFICANCE sheet associated with the laminin layer Mesothelioma (cancer of the mesothelium)  Entactin (nidogen – a glycoprotein) and perlecan (a proteoglycan with  A neoplasm that arises from surfaces of the heperan sulfate side chains) – pleural and peritoneal cavities. It is only these glycosylated proteins and occasionally found in the pericardial others serve to link together the mesothelium. laminin and type IV collagen  Commonly seen in individuals who either sheets. were exposed to asbestos or who smoke. 2. Reticular lamina – the layer below basal lamina  These are reticular fibers made of type III collagen in the underlying connective tissues by anchoring fibrils of the type VII collagen. SIMPLE SQUAMOUS EPITHELIAL CELLS  Composed of one layer of uniform flat cells, which rest on the basement membrane.  THE SIMPLEST OF THE EPITHELIA  Apical surfaces are smooth, and the width of the cells is greater than height.  FUNCTION: Allows passage of materials by diffusion and filtration in sires where Endothelial cells SIMPLE CUBOIDAL EPITHELIUM  Flattened and elongates, oriented parallel to  Composed of one layer of uniform cuboidal the direction of blood flow, and rest on a cells, which rest on the basement basement membrane. membrane.  The cells and basement membrane are  The cell’s height, width, and depth are linked by junctions called roughly equal. Nuclei are centrally placed hemidesmosomes. Beneath the basement and spherical in shape. membrane is subendothelial layer of  FUNCTION: Secretion and absorption connective tissue.  The wavy structure is called the internal elastic lamina. The endothelium, subendothelial connective tissue, and the internal elastic lamina compromise the tunica intima. Atherosclerosis  The formation of deposits of yellowish plaques that contain cholesteroal, lipid CLINICAL SIGNIFICANCE material, and lipophages (macrophage with engulfed lipids) Hyperthyroidism  These deposits, when hardened, may  Characterized by the overproduction of occlude blood flow to distant tissues, and thyroid hormoe blood clots may form on exposed collagen in o T3 and T4 (active form) subendothelial connective tissue.  Symptoms: nervousness, irritability,  Clot formation or disloged pieces of plaque tachycardia, increased perspiration, difficulty may result in vascular occlusion and stroke. sleeping, muscle weakness, warm moist  FACTORS: skin, trembling hands, and hair loss o Endothelial dysfunction,  They are thin because of its metabolic rate. dyslipidemia, inflammatory and  Seen most often but not limited to women 20 immunologic factors, and to 40 years of age. hypertension.  Type of Hyperthyroidism is Grave’s disease. Grave’s disease (diffuse toxic goiter)  The most common form of hyperthyroidism  Autoimmune disease (antibodies disease (antibodies to the TSH receptor) o Increase production of thyroid hormone.  Signs: exophthalmos  Diagnostic test: antibody test Hashimoto’s thyroiditis  Cells appear similar to stratified cells, but al cells are in contact with the basement  The most common cause of membrane. hypothyroidism  Most cells are tall columnar cells, but there  Associated with enlargement of the thyroid are also some short basal cells, some which gland (goiter) are stem cells.  Characterized by high TSH and positive TPO  The most widespread type of (thyroperoxidase) antibody (diagnostic test) pseudostratified columnar epithelium is SIMPLE COLUMNAR EPITHELIUM found in the respiratory tract and has long fingerlike, motile structures called cilia on the  Composed of one layer of columnar cells apical surface of the cells. resting on the basement membrane,  Cell’s height is greater than the width. The CLINICAL SIGNIFICANCE elongated nucleus is mosty often located in Bronchitis the basal region of the cell.  FUNCTION: absorption;secretion of mucucs,  A disease marked by acute or chronic enzymes, and other substances;ciliated type inflammation the bronchial tubes (bronchi). propels mucus (ore reproductive cells) by The inflammation may be caused by ciliary action. infection (virus, bacteria) or by exposure to  LOCATION: Can be found in the digestive irritants. tract, oviducts (fallopian tubes) in the female  In chronic bronchitis, the surface epithelium reproductive system, and ductuli efferentes may undergo hyperplasia and loss of cilia; testis of the male reproductive system. the psuedostratified epithelium is often replaced by squamous epithelium. CLINICAL SIGNIFICANCE Celiac (coelia) disease  A disorder of the small intestine  If left unteated, celiac disease can lead to malabsorbption, anemia, bone disease, and , rarely, some forms of cancer.  Histologic features: bluntings of villi, presence of lymphocytes among epithelial cells (intraepithelial lymphocytes), and increased lymphocytes within the lamina propia (connective tissue) STRATIFIED SQUAMOUS EPITHELIUM PSEUDOSTRATIFIED COLUMNAR EPITHELIUM  Contain several layers of cells in the superficial layers being flattened.  Composed of one layert of nonuniform cells  Protects the body against injury, that vary in shape and height. abrasion, dehydration, and infection  Often referred to as RESPIRATORY  May be keratinized (found in the skin – EPITHELIUM. flattened, nonnucleated dead cells-filled with tonofilaments) or nonkeratenized  (same as keratinized nut nucleated- STRATIFIED CUBOIDAL EPITHELIUM found in the linings of the oral cavity, esophagus, vagina, and tru vocal  Composed of two or three layers of cells. chords).  The top layer is columnar in shape and the  Thick membrane compose of several basal layer is usually cuboidal in shape. layer; basal cells are cuboidal or  Not a common type of epithelium. columnar and metabolically active;  Location: conjunctivitis, some large ducts in surface cells are full of keratin and dead; the exocrine glands. basal cells are active in mitosisan CLINICAL SIGNIFICANCE produce the cells of the more superficial layers. Salivary gland swelling CLINICAL SIGNIFICANCE  A clinical condition that can result from blockage of a duct or ducts, so that saliva is Psoriasis not able to exit into the mouth. This cases  A common chronic inflammatory skin the saliva back up inside the duct, resulting disease typically characterized by pink to in gland swelling. salmon colored plaques with silver scales  Most common blockage is a salivary stone and sharp margins. (calculus/calculi), which forms from salts  T-lymphocyte-mediated immunologic contained in the saliva. A blocked duct and reactions are believed to cause the clinical gland filled with stagnant saliva may become feature. infected with bacteria.  Symptoms include itching, joint pain, nail  Removal of a stone may require surgery or pitting, and nail discoloration. lithotripsy (treatment by focused, high- intensity acoustic pulses) Pathologic examination: TRANSITIONAL EPITHELIUM  Thickened epidermis  Extensive overlying parakeratotic scales  A stratified epithelium often referred to a  Microabscesses form by neutrophils in the urothelium. Lines the excretory channels stratum corneum layer. leading from the kidney (renal calyces,  Micropostules within the stratum ureters, bladder, and proximal segment or granulosumand spinosum layers. the urethra).  May contain four to six layers in the relaxed Barret Syndrome state.  Histological appearance can change when  A complication of gastroesophageal reflux stretched. disease marked by metaplasia of the SSE of  Surface cells are often described as “dome the distal esophagus into a simple columnar shaped” and are called dome cells (which epithelium as a response to prolonged may contain two nucleoli) or umbrella cells reflux-induced injury. (they contain extra cell membrane)  Patients have high risk in developing adenocarcinoma PATHOLOGIC TERMS FOR EPITHELIAL TISSUES GLANDS  Metastasis – the spread of a malignant  Glands are composed of epithelial tissue and neoplasm from its site of origin to a remote can be classified as endocrine gland and site, usually through blood and lymphatic exocrine according to how the secretory vessels. product leaves the gland.  Dyslipidemia – a general term describing a  ENDOCRINE GLANDS (no duct) -release disorder of lipoprotein metabolism causing their products into interstitial fluid or directly amounts of lipids and lipoproteins in the into the bloodstream blood; certain dyslipidemias constitures a  EXOCRINE GLANDS (has duct) – secretes major risk factor in developing their products either through ducts into the atherosclerosis such as lumen of an organ or directly onto the body hypercholesterolemia. surfaces.  Osteomalacia – abnormal bone mineralization producing weak, soft bones; Can be classified by product: may be caused by vitamin D deficiency or  Serous glands kidney disorders, including renal fanconi o A watery proteinaceous fluid (e.g. syndrome. parotid, gland of von Ebner of the  Metaplasia – the reversible process by tongue, pancreas, and sweat gland) which one mature cell type changes into  Mucous glands another mature cell type, as in squamous o Secrete mucus, a viscous mixture metaplasia of respiratory or glandular. of glycoprotein and water (e.g.  Microabscess – collection of neutrophils goblet cells in the small and large and neutrophil debris within the parakeratotic intestine, respiratory epithelium, scale in the skin disease psoriasis. some glands in hard and soft  Micropostule - collection of neutrohpils palates, and stomach epithelium). within the epidermis, abbuting the  Mixed Glands (sermucous) parakeratotic scale in the skin disease o Have both serous and mucous psoriasis. secretions (e.g. submandibular,  Parakeratosis – persistence of the nuclei of sublingual, tracheal glands) keratinocytes into the stratum corneum of  Sebaceous glands the skin or mucous membranes; o Produce lipids (e.g. skin) parakeratotic scales containing neutrophils are seen in the skin disease psoriasis. Classified by mechanism or secretion:  Merocrine (eccrine) o Most common mode o The secretory products are realesed from the cell by exocytosis without the loss of cell material (e.g. release of zymogen granules by pancreatic acinar cells)  Apocrine o The secretory product is released together with part of the apical  cytoplasm of the secretory cell (lipid  Simple coiled tubular glands secretion of the mammary gland) o Have a long duct, secretory cells  Holocrine are formed by coiled tubules o The secretory product is released  Simple acinar glands by disintegration of the entire cell. o Have short, unbranched duct; The secretory cell dies and a new secretory cells are arranged in acini secretory cell is formed froma form. nearby basal cell (e.g. sebum  Simple branched acinar glands released by the cells of sebaceous o Have a short, unbranched duct, glands). secretory cells are formed into branched acini. ADDITIONAL:  Compound tubular glands POSSIBILITIES TO PRODUCE LACTATE: o Have branched ducts, secretory cells are formed into branched - THE MOMENT TO SUCK THE BREAST tubules (e.g. brunner glands) CAN STIMULATION LEADS TO  Compound acinar glands LACTATION o Branced ducts, secretory units are - CRY OF THE BABY branced acini  Compund tubuloacinar glands Classified by morphology: o Branched ducts, secretory units are formed by both an acinar  Unicellular component and a tubular o Thesecretory products are relased component (e.g. submandibular directly onto the surface of an and sublingual glands) epithelium (e.g. goblet cell)  Multicellular o Consist of number of secretory cells arranges in different organizations that can be classifies generally, simple glands and compound glands, which can also be subclassified according to their morphology: o Branched (Compund glands) o Unbranched (Simple glands)  Simple tubular glands o Have no ducts, straight tubules and can be found in small and large intestines.  Simple branched tubular glands o Don’t have ducts, secretory cells are split into two or more tubules and can be found in the stomach.  CONNECTIVE TISSUES CELL TYPE REPRESENTATIVE REPRESANT PRODUCT OR ATIVE ACTIVITY FUNCTION  Are of mesodermal origin and consist of a Fibroblast, production of fibers Structural mixture of cells, fibers, and ground chondroblast, and ground substance. osteoblast, substance  Classification and function of connective odontoblast tissue are based on the differences in the Plasma cell Production of Immunologic composition and amounts of cells. anitbodies (defense) Lymphocyte Production of Immunologic FUNCTIONS: immunocompetent (defense) cells  Provides structural for the body. Eosinophilic Participation in Immunologic  Provide metabolic support leukocyte allergic and (defense) vasoactive CELLULAR DIFFERENTATION OF CONNECTIVE reactions, TISSUES modulations of mast cell activities and  Mesanchymal cells – fixed cells (adipocytes the inflammatory process, parasite and fibroblasts – formed and reside in the Neutrophilic Phagocytosis of Defense connective tissue) leukocyte foreign substances,  Hematopoietic stem cells – wandering cells – bacteria protection (mast cells, macrophages, plasma Macrophage Secretion of Defense cells, and leukocytes – differentiate in the cytokines and other BM and migrate from the blood circulation molecules, into connective tissues) phagocytosis of foreign substances NOTE: cells found in the CT proper includes and bacteria, antigen processing fibroblasts, macrophages, mast cells, plasma cells, and presentation to and leukocytes. Fibroblasts are responsible for other cells synthesis and maintenance of the extracellular Mast cell and Liberation of Defense material. Macrophages, plasma cells, and leukocyte, basophilic pharmacologically (participate in have defense and immune functions. active molecules allergic (e.g. histamine) reaction Adipocyte Storage of neutral Energy fats reservoir, heat  FIBROBLASTS CELL TYPE LOCATION MAIN FUNCTION  The most common cell in connective tissue Monocyte Blood Precursor of o Their nuclei are avoid or spindle macrophages shaped and can be large or small in Macrophages Connective Production of size depending on their stage of tissue, lymphoid cytokines, cellular activity organs, lungs, chemotactic bone marrow factors, and o They have pale-staining cytoplasm several other (not obvious) and contain well- molecules that developed RER and ricg Golgi participate in complexes. inflammation  FUNCTION: (defense), o Responsible for the synthesis of all antigen processing and components of the extracellular presentation matrix (fibers and ground Kupffer cell Liver Same as substance) of connective tissue macrophages Microglia cell Nerve tissue of Same as TYPES OF CONNECTIVE TISSUES the CNS macrophages Langerhans skin Antigen 1. Connective Tissue Proper cell processing and o Dense regular tissue presentation o Dense Irregular connective tissue Dendritic cell Lymph nodes Antigen o Loose Connective tissue processing and 2. Specialized Connective Tissue presentation o Adipose tissue Osteoclast Bone (fusion of Digestion of o Reticular tissue several bone macrophages) o Elastic tissue Multinuclear Connective Segregation of 3. Embryonic connective Tissue giant cell tissue (fusion of digestion of o Mesenchymal connective tissue several foreign bodies o Mucous connective tissue macrophages) 4. Supporting Connective Tissue o Cartilage o Bone MAST CELLS 5. Hematopoietic Connective Tissue  Are of bone marrow origin and are o Blood distributed chiefly around small blood o Bone Marrow vessels. MACROPHAGES  Oval and round in shape, with centrally place nucleus whose cytoplasm is filler with  Also called tissue histiocytes basophilic secretory granules an may be  Are highly phagocytic cells that are derived obscured by the cytoplasmic granules. from blood monocytes  Functions during immediate hypersensitivity  May be named differently in certain organs. reactions (occur within few minutes after penetration by an antigen of an individual previously sensitized to the same or a very similar antigen).   Mast cell granules display (hea , and pain (dolar) or redness and metachromasia – the can change the color swelling with heat and pain (rubor et tumor of some basic dyes from blue to purple or cum color et delor) last sign: loss of function red. (function laesa)  Perivascular mast cells – near small blood vessels in skin and mesenteries FIBERS  Mucosal mast cells – mucosa lining Three main types of connective tissue fibers: digestive and respiratory tracts.  Collagen fibers – formed by collagen Important molecules released from these granules o The most common and widespread includes: fibers in connective tissue  Heparin – a sulfated glycosaminoglycan that  Reticular fibers – formed by collagen acts locally as an anticoagulant o Can only be adequately visualized  Histamine – promotes increased vascular with silver stains (argyrophilic fiber) permeability smooth muscle contraction – they appear black after exposure  Serine proteases – activates various to silver salts mediators of inflammation  Elastic fibers – formed by elastin and  Eosinophil and neutrophil chemotactic fibrillin factors (ECF & NCF) –attracts leukocytes o The most numerous component of  Leukotrienes C4, D4, & E4 (or the slow- the elastic fiber system. reacting substance of anaphylaxis, SRS- o Elastin is resistant to digestion by A – also trigger smooth muscle contraction most protease but is easily hydrolyzed by pancreatic elastase. PLASMA CELLS  Derived from B lymphocytes CONNECTIVE TISSUE PROPER  Large, avoid cells that have a basophilic cytoplasm due to their richness in rough ER DENSE REGULAR CONNECTIVE  Have the ability to secrete antibodies TISSUE (primary function) that are antigen specific  Histological features include a eccentrically  Composed of coarse collagen bundles that is placed nucleus, a cartwheel pattern of densely packed and oriented into parallel chromatin in the nucleus. cylinders. Long, thin fibroblasts are found  Clock-face appearance among the fiber bundles and are oriented in  Life span: 10-20 days the same direction as the fibers.  FUNCTIONS: provides resistance to traction LEUKOCYTES forces in tendons and ligaments.  Walay gap (clear)  Considered the transient cells of connective tissue DENSE IRREGULAR CONNECTIVE  They migrate from blood vessels into TISSUE connective tissues thru diapedesis  Increase greatly during inflammation  Can be found in the mammary gland and  Recall: cardinal signs of inflammation – also in other places such as capsules of redness (rubor), swelling (tumor), colore  organs. This type of tissue is generally not a CLINICAL CORRELATION richly vascularized tissue.  Gaps (white)  WHIPPLE DISEASE  A multisystematic disease caused CLINICAL CORRELATION bn infection of Tropheryma whippleii.  HYPERTROPHIC SCARS AND KELOIDS  Primarily affects the small intestines  Are disorders caused by  Clinical symptoms accumulation of excessive amount includeabdominal pain, flatulence, of collagen deposited in the skin by malabsorption, and diarrhea hyperproliferation of fibroblasts.  The lamina propria (LCT) of the Keloid – mugawas siya small intestine reveals an increased number of macrophages. Hypertrophic – naa lg siya sulod mag scatter  TREATMENT: Penicillin  TENDINOSIS  A degenerative disease that occurs SPECIALIZED CONNECTIVE TISSUE within the substance of a tendon. Histologic exam reveals abnormal ADIPOSE TISSUE fibrotic structure including collagen  A special form of connective tissue and has disorganization, decreased fiber rich neurovascular supply. Represents 12- diameter, and increased mucoid 20% of the body weight in normal men and ground substance. 20-25% of the body weight in normal LOOSE CONNECTIVE TISSUE women.  The largest repository of energy in the body.  A very common type of connective tissue that supports many structures which are TWO TYPES OF ADIPOSE TISSUES: normally under some pressure and low 1. White Adipose Tissue friction. It is usually supports epithelial tissue, o More common type forms a layer around small blood and 2. Brown Adipose Tissue lymphatic vessels, and fills the spaces o Has abundant mitochondria thus between muscle and nerve fibers. It is the dark appearance (brown color) sometimes called AREOLAR TISSUE.  FUNCTION: Provides suspension and WHITE ADIPOSE TISSUE support for tissues that are not subjected to strong forces and forms conduits in which  Specialized for long-term energy storage vessels and nerve course.  White adipocytes are called UNILOCULAR  LOCATION: mesentery, large and small BROWN ADIPOSE TISSUE intestine  Brown adipocytes contain many small lipid inclusions and are therefore cal MULTILOCULAR  Also called the hibernating gland   Mitochondria of this type of adipose tissue ELASTIC CONNECTIVE TISSUE habe THERMOGENIN or UNCOUPLING PROTEIN (UCP-1)  Consists predominantly of elastic material,  Principal Function: Heat Production and this allows distension and recoil of o Responsible for the heat – the structure. This tissue can be found in Thermogenin (mitochondria) some vertebral ligaments, arterial walls, and in the bronchial tree CLINICAL CORRELATION CLINICAL CORRELATION OBESITY  MARFAN SYNDROME  An autosomal dominant disorder caused by  Hypertrophic obesity is a disorder FBN1 gene mutation, which affects the characterized by an increase in total body formation of elastic fibers, particularly those fat, particularly by expansion of preexisting found in the aorta, heat, eye, and skin. fat cells. Obesity increases the risk for a  Signs and symptoms include tall stature with number of conditions, including diabetes, long limbs and long, thin fingers and hypertension, high cholesterol, stroke, and enlargement of the base of the aorta coronary artery disease. accompanied by aortic regurgitation. RETICULAR TISSUE EMBRYONIC CONNECTIVE TISSUE  A specialized loose connective tissue that MESENCHYMAL CONNECTIVE provides a delicate supporting framework TISSUE for many highly cellular organs such as endocrine glands, lymphoid organs, the  Found in the developing structures in the spleen, and the liver. embryo. It contains scattered reticular fibers and mesenchymal cells, ehich have CLINICAL CORRELATION irregular, star or spindle shapes and pale- stained cytoplasm.  CIRRHOSIS  Embryonic red blood cells can be seen in  A liver disorder caused by chronic injury to this specimen. the hepatic parenchyma.  Major causes include alcoholism and chronic infection with hepatitis B or C virus. MUCOUS CONNECTIVE TISSUE  Characterized by the collapse of the delicate supporting reticular connective tissue with  Best example of mucous connective tissue is increased numbers of collagen and elastic the jellylike matrix found in the umbilical fibers. chord, WHARTON’S JELLY. This does not  Symptoms include jaundice, edema, and differentiate beyond this stage. coagulopathy. o WHARTON’S JELLY – for babies subject for transfusion PATHOLOGICAL TERMS FOR CONNECTIVE TISSUE  URTICARIA – an itchy skin eruption, also known as hives, characterized by wheals with pale interiors and well-defined red margins, often result of an allergic response to insect bites, foods, drugs.  PRURITIS – itching of the skin due to a variety of causes including hyperbilirubinemia, and allergic and irritant contact conditions.  CIRRHOSIS – an abnormal liver condition characterized by diffused nodularity, due to fibrosisand regenerative nodules of hepatocytes; frequent causes are alcohol abuse and viral hepatitis  JAUNDICE – yellow staining of the skin, mucous membranes, or conjunctiva of the eyes caused by elevated blood levels of the bile pigment bilirubin.  COAGULOPATHY – a disorder that prevents the normal clotting process of blood; causes may be acquired, such as hepatic dysfunction, or congenital, such as decreased clotting factors, as seen in inherited conditions like hemophilia.  NECROSIS – irreversible cell changes that occur as a result of cell death.  CARTILAGE AND BONE are the major components of ground substance. CARTILAGE TYPES OF CARTILAGE  A specialized (avascular) form of connective 1. Hyaline Cartilage tissue in which the firm consistency of the 2. Elastic Cartilage ECM allows the tissue to bear mechanical 3. Fibrocartilage sresses without permanent distortion.  Characterized by an extracellualar matric HYALINE CARTILAGE with glycosaminoglycans and proteoglycans that interact with collagen and elastic fibers.  The most common type of cartilage.  Consists of cells called CHONDROCYTE  Best studies among three forms. o Greek work “chondros” – cartilage  Characterized by the presence of a glassy, and “kytos” – cell) homogenous matrix that contain type II  Most cartilage is covered by a layer of dense collagen which is evenly dispersed within the irregular connective tissue (Perichondrium). ground substance.  Most of the hyaline cartilage is covered by CARTILAGE CELLS the perichondrium except the articular surface of joints. MAIN TYPES OF CARTILAGE CELLS  LOCATION: articular surfaces of the 1. Chondrogenic cells movable joints, walls of larger respiratory  Located in the perichondrium and passages (nose, larynx, trachea, bronchi), differentiate into chondroblasts to ventral ends of ribs, and epiphyseal plate. participate in appositional growth of  It is the template for endochondral bpne cartilage. formation. 2. Chondroblasts ELASTIC CARTILAGE  Are young chondrocytes, which derive from chondrogenic cells, and  Is essentially very similar to hyaline cartilage are able to actively manufacture except that it contains an abundant network cartilage matrix. of fine elastic fibers in addition to collagen 3. Chondrocytes type II fibrils.  Mature chondroblasts that are  LOCATION: auricle of the ear, walls of the embedded in the lacunae of the external auditory canals, auditory tubes, matrix. epiglottis, cuneiform cartilage in the larynx. CARTILAGE MATRIX FIBROCARTILAGE  The matrix of cartilage is  It is the tissue intermediate between dense nonmineralized and consists of connective tissue and hyaline cartilage. fibers and ground substance.  There is no distinct percihondrium in  Collagen fibers are mainly type II in fibrocartilage. the matrix.  LOCATION: intervertebral cartilage, pubic  Glycosaminoglycans, symphysis. proteoglycans, and glycoproteins  CHONDROGENESIS  Contains crystalline mineral salts, mostly of calcium and phosphorus. 1. Appositonal Growth  Growth begins with the TYPE GROSS CHARACTERI MAIN MAIN OF APPEARAN STICS LOCATION FUNCTION chondrogenic cells located in the BONE CE perichondrium. Most important type CLASSIFICATION BASED ON GROSS APPEARANCE because most cartilage growth in Compa Uniform; no Higher Outer Protection the body is this type of growth. ct trabeculae density; portion of and support 2. Interstitial Growth bone and lamellae the bone spicules arranged in (cortical  Resulting from the mitotic division circular bone) of preexisting chondrocytes. Occurs pattern during the early phase of cartilage Cancel Irredular Lower Inner Support; formation. Also occurs in the lous shape; density; cone of blood cell epiphyseal plates of long bones. (spong trabeculae lamellae the bone production y and arranged in (medullar  Important in increasing long bone bone) spicules parallel y bone) length. present; pattern surrounded BONE by the BM cavities  A specialized connective tissue composed of Long Longer Consists of Linbs and Support calcified, mineralized intercellular matrix bone rather than diaphysis fingers and called BONE MATRIX. wide (long shaft) movement  OSTEOCYTES – found in the cavities and two epiphyses at between layers of bone matrix. the ends  OSTEOBLASTS – which synthesize the Short Short, cube A thin layer of Wrist and Movement organic components of the matrix. bone shaped compact ankle  OSTEOCLASTS – which are multinucleated bone outside bones giant cells involved in the resorption and and thick cancellous remodeling of the bone tissue. bone inside Flat Flat, thin Two parallel Many Support, BONE MATRIX bone layers of bones of protection compact the skull, of brain and  Primarily contains calcium, phosphate, other bone ribs, other soft organic and inorganic materials, and type I separated by scapulae tissues; collagen fibers. a layer of blood cell 1. Organic (noncalcified) matrix cancellous production  Mainly type I collagen with bone Irregul Irregular Consists of Vertebrae Support, mineralized ground substance ar shape thin layer of and bone protection (chondroitin sulfate and keratin bone compact of the of the sulfate) bone outside pelvis spinal  Found in the osteoid which is and chord and produced by osteoblasts. cancellous pelvic bone inside viscera; 2. Inorganic (calcified) matrix blood cell  Mainly in the form of production hydroxyapatite.