Male Reproductive System PDF

SPECIAL HISTOLOGY Male Reproductive System Dra. Sabina Sanegre Dept. Ciencias Biomédicas [email protected]  MALE REPRODCUTIVE SYSTEM TESTES - Seminiferous tubules - Straight tubules - Rete testis EXCURRENT DUCT SYSTEM - efferent ductules - epididymis - Duct...

SPECIAL HISTOLOGY Male Reproductive System Dra. Sabina Sanegre Dept. Ciencias Biomédicas [email protected]  MALE REPRODCUTIVE SYSTEM TESTES - Seminiferous tubules - Straight tubules - Rete testis EXCURRENT DUCT SYSTEM - efferent ductules - epididymis - Ductus deferens ACCESSORY SEX GLANDS - seminal vesicle - prostate - Bulbourethral glands PENIS 4 Testicles - Anatomy 7 Testes Stroma - Surrounded by the tunica albuginea (irregular dense CT), it widens at the back to form the testicular mediastinum, traversed by vessels and by the sperm pathways. This tunic emits connective tissue septa inwards forming about 250 compartments called lobules. - Vascular tunic, loose areolar CT below the previous one, with collagen, fibroblasts, macrophages and mast cells and vessels. - Leydig (L) or interstitial, polyhedral and acidophilic cells, synthesize testosterone. Characteristic intracytoplasmic mass (Reinke's crystalloid (CR)). -Peritubular myoid cells (produce peristaltic contractions). They are responsible for mobilizing both sperm and testicular fluid along the seminiferous tubules to the sperm pathways. 8 Testes 9 Testes Parenchyma Seminiferous tubules, each 30-70 cm long, highly contoured (combined length of all seminiferous tubules of each testis =300-900 m), in which spermatogenesis takes place. Structure: seminiferous or germinal epithelium (spermatozoa) which is composed of two cell groups, proliferating cells, (spermatogenic) and a non-proliferating, supporting population (Sertoli cells), which are phantom cells on the periphery of the tubule, eosinophilic cytoplasm. Other functions: phagocytic (of residual bodies during spermiogenesis) and secrete other substances. They rest on a well-defined basement membrane. 11 Testes Parenchyma 13  INTRATESTICULAR DUCTS Straight tubules, rete testis - Straight tubules, epithelium consisting only of Sertoli cells. They are very short and when they reach the testicular mediastinum they join together to form the Rete testis, or Haller's network, which is a system of anastomosed tubules formed by a simple cubic epithelium with microvilli. 18 INTRATESTICULAR DUCTS - Straight tubules, rete testis 19 INTRATESTICULAR DUCTS - Rete testis EXCURRENT DUCT SYSTEM - Efferent ductules: Cylindrical epithelium - pseudostratified. With high cylindrical cells (with cilia) and low cylindrical cells (with microvilli). Thin layer of smooth muscle. It is in this portion of the pathway that most of the testicular fluid is reabsorbed. - Epididymis: It is formed by the fusion of efferent ducts. It is a single, tightly coiled tubule (4-6 m). Spermatozoa mature, they acquire motility. Cylindrical epithelium pseudostratified with long stereocilia. Areas: head, body and tail. Surrounded by thickening muscle. 21 EXCURRENT DUCT SYSTEM - Efferent ductules and epididymis 22 EXCURRENT DUCT SYSTEM - Epididymis 23 EXCURRENT DUCT SYSTEM - Ductus deferens, cylindrical epithelium pseudostratified with stereocilia. Reduced and folded lumen due to the presence of three layers of muscle: thinner inner longitudinal layer, thicker middle circular and thick longitudinal outer layer, has to displace sperm to the urethra during ejaculation. 26 DUCT SYSTEM - Ductus deferens Rodríguez, M. L. (2015). Compendio de histología médica y biología celular. [ClinicalKey Student]. 27 ACCESSORY SEX GLANDS Seminal vesicle Two elongated, tortuous tubular glands, but it's a single, tightly folded tubular lumen. In histological preparations, the lumens are sometimes occupied by an eosinophilic proteinaceous material. 28 ACCESSORY SEX GLANDS Seminal vesicle - Mucosa with abundant folds, with pseudostratified - cylindrical epithelium. High cells have secretory activity and do so by apocrine mechanisms. - A layer of smooth muscle distributed in an inner circular layer and an outer longitudinal layer, and a fibrous layer. It contracts during ejaculation. - Secretory function under hormonal control of testosterone. - Does not store sperm except in pathological conditions. 29 ACCESSORY SEX GLANDS Prostate - Around the prostatic portion of the urethra. - Comparable in size to a walnut, and surrounded by a fibroelastic capsule from which septa depart, dividing it into poorly defined lobes. - Cylindrical epithelium - pseudostratified. Transition near the urethra. - Fibromuscular stroma (smooth muscle cells and fibrocytes). - It depends on the stimulation of testosterone for proper function. - Parenchyma (formed by apocrine tubuloalveolar prostate glands that are organized into three concentric layers): Peripheral glands: the + extensive, are the main ones. They open to the urethra through long ducts. Submucosa glands/central:: open into the urethra through short ducts. Mucosa glands/periuretral: open directly into the urethra. 32 ACCESSORY SEX GLANDS Prostate 33 ACCESSORY SEX GLANDS Prostate The histological features that allow the identification of the prostate are: glands with wide lumen surrounded by a fibromuscular stroma. The glandular lumens usually contain some stored secretions; In the elderly, small starchy spherical bodies are observed (corpora amylacea), consisting mainly of condensed and often calcified glycoproteins. James S. Lowe, Peter G. Anderson y Susan I. Anderson., 2020 http://wzar.unizar.es/ 35 ACCESSORY SEX GLANDS Prostate 36 ACCESSORY SEX GLANDS Bulbourethral or Cowper glands - Tubuloalveolar glands composed of a cubic to cylindrical epithelium of secretory activity, also dependent on testosterone. Mucous secretion. 37 PENIS It consists of two dorsal masses of erectile tissue (corpora cavernosa), and a ventral mass (corpus spongiosum), which participates little in erection but avoids compression of the urethra during erection. Spongy urethra inside the corpus spongiosum, small periurethral or Littré's glands (mucous secretion) may be found. 38 PENIS 39 PENIS Tunica albuginea: A layer of dense, irregular CT that surrounds each of the three structures. Septum of the penis: separation between the corpora cavernosa and with the same characteristics of the tunica albuginea. Corpora cavernosa formed by vascular spaces lined with endothelium (they will fill with blood during erection), separated from each other by smooth muscle trabeculae and connective tissue. Glans and foreskin: thin skin without hair follicles. On the inside of the foreskin there are preputial sebaceous glands or Tyson's glands (fatty secretion). 40  Epididymis Efferent Deferent Prostate Urethra James S. Lowe, Peter G. Anderson Seminiferou y Susan I. Anderson., 2020 s Seminal v 42  Key Ideas Structure of testis Stromal and parenchymal elements and function of each Characteristics of the different duct system Characteristics of the different accessory sex glands Structure of the penis Identifica: espermatogonias espermatocitos espermátidas espermatozoides células de Sertoli THANK YOU ALL FOR THE WONDERFUL CLASSES!!! 53