MALE REPRODUCTIVE SYSTEM.
TESTIS. = TS. TS is composed of 250 LOBULES.
LOBULE is composed of 2 components: 1) tubular comp., 2) intertubular component
Tubular comp. presented by 1-4
convoluted seminiferous tubules = (CST).
Main
function of
CST – it is place of
SPERMATOGENESIS.
Wall of
CST is composed of: a) tunica propria (L.I.C.T. + MYOID cells), b)
Seminiferous epithelium. = (
SE ). Stratified
SE contains
2 different populations of cells:
A)
SERTOLI cells=
sustentacular cs, B)
SPERMATOGENIC cells: - spermatogonia, - spermatocytes, - spermatids, -
spermatozoa.
SERTOLI cell – is irregular-shaped EPITHELIAL cell INTO wall of CST. It has: a) 2 LATERAL
processes, b) invaginations of plasma membrane.
Spermatogenic cells locate in these
invaginations. Invaginations a namely are a tissue place for
SPERMATOGENESIS. Mature spermatozoa detache from Sertoli cell and move along genital ducts. Funct. of Sertoli cells:
1)
barrier funct. - bv lateral processes cells form
«Sertoli - Sertoli» zonule occludentes. It are main component of BLOOD-TESTIS BARRIER. Barrier prevents destruction of spermatozoa by T-killer cells, 2) It phagocytise abnormal spermatozoa, 3) Secrete ABP-protein, 4) Secrete antimullerian hormone in embryo, 5) It gives
nutrients to spermatogenic cells (transferrin)
Intertubular component presented by: a) capillaries,
b) INTERSTITIAL ENDOCRINE cell s= LEYDIG cells.
It are: a) locate in lobule
between CSTs, b) round-shaped with acidophilic cytoplasm.
Funct.: LEYDIG cells secrete hormone
TESTOSTERON.
EPIDIDYMIS. = (ED)
ED has: head, body, tail. Body and tail are composed of highly convoluted
DUCTUS epididymis.
Lumen of ductus epididymis contains
seminal fluid.
Wall of DUCTUS epididymis contains 3 tunics: 1) T. MUCOSA, 2) T. muscularis, 3) T.adventitia.
Tunica
mucosa is composed of: a) simple columnar
PSEUDOSTRATIFIED epithelium, b) lamina propria (L.I.C.T.). Epithelium contains 2 cell types: a) Principal cs, b) basal cs.
Principal cs – are tall columnar, with apical STEROCILIA (nonmotile microvilli). Funct.:
a) it absorb plasma of seminal fluid, thus promoting
STORAGE of spermatozoa,
b) secrete glycoproteins for formation of
glycocalyx around sperm.
T. muscularis is composed of circular layer of smooth muscle cells
T.adventitia is loose irreg .connec .tiss.
PROSTATE GLAND. = (PG).
ATTENTION: PG on cross section contains
2 ORGANS, because
URETHRA passes inside
of PG. Urethra is lined by
TRANSITIONAL epithelium.
Structure of PG on cross section:
1) Capsule (dense irregular connect. tiss. + a lot of smooth MUSCLE cells), 2)
3 groops of
concentrically arranged
PROSTATIC glands, 3)TRANSITIONAL epithelium in centre.
Each PROSTATIC gland is small compound tubuloalveolar
exocrine gland:
A) MUCOSAL (internal) glands, B) SUBMUCOSAL (intermediate) glands,
C)
MAIN (peripheral) glands. Amount of MAIN glands is 30 to 50. It constitute 75% of parenchyma. Each gland has: a) duct, b) secretory portion. Duct emptys into urethra.
Secretory portion is composed of simple columnar epithelium. It contains 3 cell types:
a) Chief cells - are tall columnar with apical secretory
granules. Funct.: secretion of seminal fluid components (fibrinolysin, citric acid, phosphatase), b) short basal cells- are origin for regeneration,
c) endocrine cells. Funct.: secretion of hormones prostaglandins.
Stroma of PG locates between prostatic glands. STROMA is composed: a) smooth
muscle cells,
and b) elastic fibres. Stroma and capsule are able to CONTRACT during ejaculation.
Составитель – доцент В.В. Бондаренко.