Endocrine System PDF

Endocrine System MODULE 2  Endocrine consists of glands that synthesis and secrete hormones directly into the blood stream Endocrine Endocrine system vs Exocrine system? System Endocrine Exocrine Hormone...

Endocrine System MODULE 2  Endocrine consists of glands that synthesis and secrete hormones directly into the blood stream Endocrine Endocrine system vs Exocrine system? System Endocrine Exocrine Hormones Electrical impulses More generalized More specific response response Longer duration Shorter duration Location of the Endocrine Glands  Secrete hormones (chemical messengers) directly into the bloodstream Endocrine These hormones coordinate and direct Gland activities of specific target cells or organs Activities Each gland releases a specific hormone or hormones and generates specific effects  Chemical messengers Made from proteins or steroids Steroid hormones include the sex Hormones hormones and the adrenal cortex hormones Hormones react with specific target tissues  Negative feedback ◦Hypothalamus ◦Direct on gland Control of Tropic hormones Hormone ◦Secretion is controlled by other release: hormones ◦TSH---TH Nerve stimulation ◦Adrenal medulla  Hypothalamus of brain is main integrative center for the endocrine and Role of the autonomic nervous systems Hypothalam us Helps control some endocrine glands by on the neural and hormonal pathways Endocrine Also exerts hormonal control at anterior System pituitary gland, by releasing and inhibiting hormones and factors  Stimulate the pituitary gland to synthesize and release trophic hormones, which include: Hypothalami ◦Corticotropin (adrenocorticotropic c Hormones hormone) ◦Thyroid-stimulating hormone ◦Gonadotropins (luteinizing hormone and follicle-stimulating hormone) Hypothalamus and Pituitary T H E R E L AT I ON S H I P B E T W E E N T H E H Y P OT H AL A M U S AN D T H E PO S T E R IO R LO BE OF T H E P IT U I TA RY GL A N D Hypothalamus and Pituitary T H E R E L AT I ON S H I P B E T W E E N T H E H Y P OT H AL AM U S AN D T H E A N T E R I O R LO BE OF T H E P IT U I TA RY GL A N D  Anterior pituitary ◦Growth Hormone (GH)-dwarfs, giants and acromegaly ◦Thyroid Stimulating Hormone (TSH) ◦Adrenocorticotropic Hormone (ACTH) Pituitary ◦Gonadotropic Hormone-FSH, LH Gland ◦Prolactin Posterior Pituitary ◦Antidiuretic hormone (ADH) ◦ Vasopressin ◦ Diabetes Insipidus ◦Oxytocin  Secreted by anterior pituitary gland in response to growth hormone-releasing hormone (GHRH) – recombinant form is somatotropin Growth Hormone Promotes protein synthesis in cells, increases fat mobilization, use of fatty acids for energy Prescribed for dwarfism  Secreted by anterior lobe of pituitary gland; it controls the release of thyroid hormone Thyroid- Stimulating It is necessary for the growth and Hormone function of the thyroid gland It is prescribed for hypothyroidism  Also from anterior pituitary gland; stimulates growth of the adrenal gland cortex and the secretion of corticosteroids Adrenocorticotr ACTH is used generally for diagnostic opic Hormone testing, and not for therapeutic purposes Adverse effects include: Insomnia Acne Delayed wound healing Increased risk of infection  A gonadotropin that stimulates the growth and maturation of follicles in the ovary Follicle- Promotes spermatogenesis (by which Stimulating male gametes develop into mature Hormone spermatozoa in the male) It is secreted by the anterior pituitary gland  Secreted by the anterior lobe of the pituitary gland that is necessary for proper reproductive function Luteinizing In females, an acute rise of LH triggers Hormone ovulation In males, LH is also known as interstitial cell-stimulating hormone; it stimulates the production of testosterone  Primarily associated with lactation Secreted from the anterior pituitary gland Prolactin Released via thyrotropin-releasing factor In adults, hyperprolactinemia and galactorrhea can result from adenomas that secrete excessive prolactin  Released when body is low on water, and causes the kidneys to conserve water (but not salt) by concentrating the urine and reducing urine volume Antidiuretic Also called vasopressin or ADH Hormone Raises blood pressure via vasoconstriction Released from the hypothalamus and stored in the posterior lobe of the pituitary gland  Also acts as a neurotransmitter in the brain Mostly manufactured by the hypothalamus Oxytocin Released in women during labor and lactation Also released by both sexes during orgasm Greatly stimulates uterine contractions; used IV to induce or reinforce labor  Thyroid Hormone (TH) ◦made from iodine Thyroid ◦negative feed back Gland ◦Goiter, cretinism, myxedema, hyperthyroidism Thyroid and Calcitonin Parathyroid Gland Parathyroid Hormone (PTH)  Cortex Mineralocorticoids aldosterone Glucorticoids cortisol Adrenal Gonadocorticoids Gland Addison’s and Cushing’s Disease Medulla Extension of the sympathetic nervous system  Norepinephrine (noradrenaline) is released from the medulla of the adrenal glands Norepinephri ne It supports the “fight-or- flight” response by: Increasing heart rate Triggering the release of glucose Increasing skeletal muscle readiness