Histology of Male Reproductive System

HISTOLOGY OF MALE REPRODUCTIVE SYSTEM  Matheus Components: Testes  produces the male gametes; secretes testosterone Penis  organ of copulation Genital ducts  collects, stores & conducts spermatozoa from testes Accessory glands  secretes seminal fluid

SPERMATOCYTE PRIMARY Spermatocyte >largest spermatogenic cell >copious cytoplasm >large nucleus w/ chromatin strands

SECONDARY Spermatocyte >spherical/polygonal >small dark sstaining nucleus w/ fine granular chromatin >few are seen in section nd >rapidly undergo 2 meiotic division

SERTOLI CELLS supporting cells junctional complex b/w sertoli cell & adjacent germ cell o zona adherens o site of blood testis barriers o divides the seminiferous tubule into basal & luminal compartments o provides nourishment to the developing spermatogenic cells

TESTIS -

paired ovoid organs, lie within the scrotum covered by a capsule made up of 3 layers: o T. Vaginalis – outer; lower expanded part of processus vaginalis o T. albuginea – middle; made of dense fibrous tissue  *divider b/w lobules = septuli testis o T. vasculosa – inner; with blood vessels Each lobule of the testis is consists of: o 1-4 seminiferous tubules o Connective tissue stroma –  (+) interstitial tissue containing LEYDIG CELLS  Large, polygonal, eosinophilic cells producing testosterone SEMINIFEROUS EPITHELIUM o Thin basement membrane  stratified epithelium o 2 basic cell types  Spermatogenic cells (round nucleus)  Sertoli cells or Sustentacular cells (pyramidal lobules) o Spermatogenic cells  Spermatogonia  Primary spermatocyte  Secondary spermatocyte  Spermatid  Sperm cell o Sertoli Cells  Columnar cells SPERMATOGONIA o Location: beneath basement membrane of seminiferous tubule TYPE A spermatogonia TYPE B spermatogonia >large oval nucleus w/ fine >spherical nucleus w/ chromatin granules dispersed heavy stained >homogenous pale staining chromatin masses cytoplasm >central nucleoli >peripheral nucleoli >give rise to primary >give rise to either Type A/B spermatocyte spermatogonia

EGBautistaII

SPERMATOGENESIS 1. Golgi apparatus elaborates the acrosomal vesicle 2. Acrosomal vesicle becomes applied to one pole of the elongating nucleus; forming the acrosomal head cap 3. Centrioles migrate to the opposite pole; elongates to form a flagellum st 4. cytoplasm migrates to surround 1 part of flagellum

FACTORS AFFECTING SPERMATOGENESIS 1. dietary deficiencies 2. infection 3. elevated testicular temperature 4. steroid hormones 5. toxic agents 6. radiation

SPERM CELLS a mature sperm cell actively matolie, free swimming consists of: o head o middle piece o body o tail Quiescent in the seminifeous tubule & ducts of the testes o Become active by the secretion of the accessory glands Production begins at puberty

HORMONAL REGULATION OF MALE REPRODUCTIVE SYSTEM ANTERIOR PITUITARY GLAND/ Adenohypophysis FSH  stimulates spermatogenesis LH/ ICSH  stimulates Leydig’s cells to secretes testosterone

SPERMATOGENESIS process by which spermatogonium develop into a spermatozoa (approx. 74 days) has 3 phases: o SPERMATOGONIAL PHASE  Stem cells divide to replace themselves & provide a population of committed spermatogonia (mitosis) o SPERMATOCYTE PHASE  Primary spermatocytes undergo meiosis to reduce both the chromosomes & amount of DNA o SPERMATID PHASE (Spermiogenesis)  Spermatids are transformed directly into spermatozoa SPERMATOGENIC CELLS Spermatogonia stem cell, diploid chromosomes (46 chromosomes or 44 XY) PRIMARY spermatocyte – 44XY SECONDARY spermatocyte – 22x/22y or haploid/ 23 chromosome SPERMATID – 22x/ 22y SPERM cell – 22x/ 22y

TESTICULAR DUCTS 1. Tubuli recti  LE: Simple cuboidal epithelium 2. Rete testis  LE: Simple cuboidal epithelium 3. Ductuli efferentis a. LE: alternating simple tall columnar ciliated cells & low columnar non ciliated cells b. Lumen is irregular & described as “FESTOONED appearance” c. Cilia  help in transporting spermatozoa to epididymis

EPIDIDYMIS -

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crescent-shaped structure divided into: head, body & tail site of storage & mature sperm cell LE: Pseudostratified columnar epithelium w/ stereocilia 3 cells: o Principal cells o Basal cells o Halo cells  small cells w/ pale staining cytoplasm & dark staining nuclei  An intraepithelial lymphocyte Spermatozoa undergo additional physiological maturation (capacitation) & gain fertilizing capacity & motility

VAS DEFERENS -

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direct continuation of the tail of the epididymis LE: pseudostratified columnar epithelium Tunica muscularis  gives the vas deferens firm consistency & the thickest layer o Inner longitudinal o Middle circular o Outer longitudinal Tunica adventitia o Loose fibroelastic connective tissue that blend with the tissue of spermatic cord o CORD  enclosed by cremaster muscle

EJACULATORY DUCT -

formed by the union of the ampulla of vas deferens & excretory ducts of the seminal vesicle opens into the prostatic utricle LE: pseudostratified columnar epithelium

SEMINAL VESICLE -

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paired, elongated & highly folded tubular glands LE: pseudostratified columnar epithelium Mucosa is thrown into numerous primary, secondary & tertiary folds  to increase surface area for secretion Tunica muscularis o Inner circular o Outer longitudinal Tunica adventitia  dense connective tissue Secretes whitish yellow, viscous material containing fructose & prostaglandin

PROSTATE GLAND -

largest accessory gland consists of 30-50 tubuloalveolar gland LE: pseudostratified columnar epithelium Secretes acid phosphatase, citric acid & amylase Calcified secretions  prostatic concretions/ corpora amylacea o It neutralize the acidity of the vagina

BULBOURETHRAL (COWPER’s) GLAND -

pair of small compound, tubulo alveolar glands embedded in the urobulbourethral gland LE: either psudostratified columnar or cuboidal epithelium Secretes alkaline fluid & mucous o Neutralize urine in the penile urethra o Act as lubricant

EGBautistaII

PENIS -

formed primarily of 3 cylindrical masses of erectile tissue note the paired corpora cavernosa & the ventrally placed corpus spongiosum containing the urethra a dense fibroelastic tissue, the Tunica albuginea, binds the 3 together & forms a caplsule around each corpus spongiosum, like cavernosa, spaces are lined by endothelium w/c is continuous with arteries & veins

.Prostate .Membranous .Fossa Navivularis

 transitional  pseudostratified columnar  SSNKE

SEMEN from testis & secretory products, from epididymis, vas deferens, prostate, seminal vesicles & bulbourethral gland alkaline pH to neutralize the acid environment of vagina Average ejaculation has volume of about 3ml & normally contains up to 100 million sperm/ ml.