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Male reproductive systemMale reproductive systemThe male reproductive system is composed of The male reproductive system is composed of A) A) The testes (Male gonads):The testes (Male gonads):The testes are the The testes are the primary sex organsprimary sex organs in males .they in males .they have two functions :have two functions :Exocrine function (Spermatogenesis) sperm Exocrine function (Spermatogenesis) sperm formationformation . .Endocrine function:Endocrine function: secretion of hormones: secretion of hormones: Testosterone ,the principle male sex hormone .Testosterone ,the principle male sex hormone .Inhibin & estrogen refer to spermatogenesis .Inhibin & estrogen refer to spermatogenesis .The The secondary (Accessory ) sex organssecondary (Accessory ) sex organs::1- Epididymis1- Epididymis: a single coiled tube in which sperms : a single coiled tube in which sperms are stored continue their maturation ,become motile and are stored continue their maturation ,become motile and acquire the power of fertilization .acquire the power of fertilization .2- 2- vas deferencs:vas deferencs: a long duct which store & a long duct which store & Transports sperms from the tail of the epididymis to the Transports sperms from the tail of the epididymis to the ejaculatory ducts.ejaculatory ducts.3- Seminal vesicle3- Seminal vesicle: One on each side of the prostate : One on each side of the prostate ..Act as a gland .it does not secret sperms ,secret Act as a gland .it does not secret sperms ,secret mucoid viscid fluid rich in mucoid viscid fluid rich in fructose ,prostaglandin ,fibrinogen and ascorbic acids fructose ,prostaglandin ,fibrinogen and ascorbic acids Fructose a nutrient for ejaculated spermsFructose a nutrient for ejaculated spermsProstaglandins aid fertilization by causing reverse Prostaglandins aid fertilization by causing reverse peristalsis in the uterus & fallopian tube peristalsis in the uterus & fallopian tube

4- 4- Prostate glandsProstate glandssecrete alkaline milky fluid to neutralize the acidity of secrete alkaline milky fluid to neutralize the acidity of

vagina and male urethra , vagina and male urethra , 5-Bubo urethral glands (Cowper's glands):5-Bubo urethral glands (Cowper's glands): secrete mucus which is discharged into the penile secrete mucus which is discharged into the penile urethra during excitements . urethra during excitements .

The testesThe testesThe testes consists of :The testes consists of :a- a- seminiferous tubulesseminiferous tubules: lined with 2 type of : lined with 2 type of cells :cells :- Spermatogonia : form the sperm .- Spermatogonia : form the sperm .Sertoli cells : are large cells that extend from the Sertoli cells : are large cells that extend from the basement membrane of the seminiferous tubule to basement membrane of the seminiferous tubule to the lumen and envelop the developing germ cells the lumen and envelop the developing germ cells b- b- Interstitial cell of leygigInterstitial cell of leygig ; secrete the male ; secrete the male sex hormone testosterone .sex hormone testosterone .

Functions of the testesFunctions of the testes

SpermatogenesisSpermatogenesis

Is the formation of the spermatozoa from the Is the formation of the spermatozoa from the primitive germ cells (spermatogonia ) .This takes primitive germ cells (spermatogonia ) .This takes 74 74 days to form a mature sperm.days to form a mature sperm.Spermatogenesis begins at puberty and continues Spermatogenesis begins at puberty and continues throughout life .throughout life .

Stages of spermatogenesisStages of spermatogenesis: : Spermatogenesis is divided into 3 stages:Spermatogenesis is divided into 3 stages:1- spermatocytogenesis1- spermatocytogenesis

Formation of primary spermatocyte from spermatogonia( 4mitotic division Formation of primary spermatocyte from spermatogonia( 4mitotic division ))2- Meiosis (reduction divipsion )2- Meiosis (reduction divipsion )

Primary spermatocyte is converted into secondary by the process of Primary spermatocyte is converted into secondary by the process of meiosis meiosis 3- spermiogenesis3- spermiogenesis

Maturation of spermatid to form sperm . It occure in cytoplasmic fold Maturation of spermatid to form sperm . It occure in cytoplasmic fold of sertoli cellof sertoli cell

Factor affecting spermatogenesisFactor affecting spermatogenesis

Hormonal factorHormonal factor (Anterior pituitary hormones) (Anterior pituitary hormones)Pituitary gonadotropinPituitary gonadotropin

Follicular stimulating hormone (FSH)Follicular stimulating hormone (FSH) It stimulate gametogenic function of the testes ,it stimulate growth & It stimulate gametogenic function of the testes ,it stimulate growth &

secretion of setoli cells ,this results in secretion of setoli cells ,this results in Conversion of spermatids into sperm (spermiogenesis ) Conversion of spermatids into sperm (spermiogenesis )

Lutenizing hormone (LH = ICSH) Lutenizing hormone (LH = ICSH) Stimulate testosterone secretion by leydig cells ,increased number of Stimulate testosterone secretion by leydig cells ,increased number of

interstitial cell of leydig.interstitial cell of leydig.2- testosterone ; required for complete meiotic division of primary 2- testosterone ; required for complete meiotic division of primary

spermatocyte to form secondary spermatocyte, then finally maturation spermatocyte to form secondary spermatocyte, then finally maturation of spermatid to form sperm.of spermatid to form sperm.PROLACTIN & growth hormonePROLACTIN & growth hormone : its role is not known. : its role is not known.

Other hormonesOther hormonesTestosteroneTestosterone ; ;

Complete meiotic division of primary spermatocyte to form secondary spermatocyte.Complete meiotic division of primary spermatocyte to form secondary spermatocyte.Maturation of spermatid to form sperm.Maturation of spermatid to form sperm.

Oestrogen;Oestrogen;Decrease FSH secretion so inhibit spermatogenesis.Decrease FSH secretion so inhibit spermatogenesis.

Thyroxin;Thyroxin;

Increase metabolisim so stimulate spermatogenesis.Increase metabolisim so stimulate spermatogenesis.

Inhibin Inhibin : inhibit FSH by direct effect on the anterior pituitary this negative feed back : inhibit FSH by direct effect on the anterior pituitary this negative feed back mechanism control spermatogenesis.mechanism control spermatogenesis.

ActivinActivin ; Formed from inhibin precursor .Activin stimulate FSH secretion ; Formed from inhibin precursor .Activin stimulate FSH secretion

DietDietAbalanced diet containing adequate amount of proteins and vitamins (A,B,C,E)Abalanced diet containing adequate amount of proteins and vitamins (A,B,C,E)

Starvation;Starvation; decrease FSH&LH so arrest spermatogenesis decrease FSH&LH so arrest spermatogenesis

Protein defficiency;Protein defficiency; arrest spermatogenesis arrest spermatogenesis

Vitamin E deficiencyVitamin E deficiency ;in rate lead to tubular degeneration but not proved in man . ;in rate lead to tubular degeneration but not proved in man .

Vitamin B Complex;Vitamin B Complex; need in metabolic activity in general but not specific for need in metabolic activity in general but not specific for spermatogenesis .spermatogenesis .

Vitamin B 12;Vitamin B 12;Stimulate nuclic acid synthesis ,need for spermatogenesis Stimulate nuclic acid synthesis ,need for spermatogenesis

TemperatureTemperatureThe optimum temperature for spermatogenesis is 35 it is kept at these The optimum temperature for spermatogenesis is 35 it is kept at these temperature due to scrotal skin is thin ,rich in sweat glands and contain little temperature due to scrotal skin is thin ,rich in sweat glands and contain little subcutaneous fat.subcutaneous fat.

Also in cold weather reflex contraction of scrotal muscle to pull the testes Also in cold weather reflex contraction of scrotal muscle to pull the testes close to the body ,but in hot weather relaxation of dartos muscle close to the body ,but in hot weather relaxation of dartos muscle

Cryptorchidism (Undescended testes)Cryptorchidism (Undescended testes)

Failure of the testes to descend from the abdomen to scrotum cause Failure of the testes to descend from the abdomen to scrotum cause degeneration of tubular epithelium and sterility .spermatogenesis fails but degeneration of tubular epithelium and sterility .spermatogenesis fails but testosterone secretion continues testosterone secretion continues

Fever or hot baths for 30 minutes reduce the sperm count in males. Fever or hot baths for 30 minutes reduce the sperm count in males.

Irradiation Irradiation Atomic radiation and large doses of x –rays cause irreversable damage of Atomic radiation and large doses of x –rays cause irreversable damage of germinal epithelium germinal epithelium

Other factorsOther factors

O2 lack ,bacterial toxins and chemical toxins depress spermatogenesis .O2 lack ,bacterial toxins and chemical toxins depress spermatogenesis .

Sertoli cellsSertoli cells

Sertoli cells are large cells that extend from the basement membrane of the Sertoli cells are large cells that extend from the basement membrane of the seminiferous tubule to the lumen of the tubuleseminiferous tubule to the lumen of the tubule

Function of sertoli cells:Function of sertoli cells:1- Nurse cells1- Nurse cells; Sertoli cells are called nurse cells because they support and nourish ; Sertoli cells are called nurse cells because they support and nourish spermatocytes ,spermatids and spermatozoa ,due to their high glycogen content .spermatocytes ,spermatids and spermatozoa ,due to their high glycogen content .

22 - -spermiationspermiation ; Release of mature sperms from the setoli cells to become free in the tubular lumen.under ; Release of mature sperms from the setoli cells to become free in the tubular lumen.under the controlled of LHthe controlled of LH. .

3-Secretion 3-Secretion : FSH stimulate setoli cells to secrete ;: FSH stimulate setoli cells to secrete ;

aa) Androgen binding protein) Androgen binding protein (ABP); (ABP); act as a carrier of testosterone from tests to epididymis. act as a carrier of testosterone from tests to epididymis.

B) B) Mullerian inhibiting substanceMullerian inhibiting substance : it cause of regression of mullerian ducts in male during fetal life . : it cause of regression of mullerian ducts in male during fetal life .

CC) Inhibin) Inhibin;; inhibit FSH by direct feed back effects from hypothalamus . inhibit FSH by direct feed back effects from hypothalamus .DD) Estrogen.) Estrogen.

4- Blood – testes Barrier4- Blood – testes Barrier : : IS a memberane formed by the tight junction between the IS a memberane formed by the tight junction between the

basis of setoli cells basis of setoli cells .Functions;.Functions;A) protect germ cells from injurious substance in the blood ( circulating immunoglobulin's that may affect A) protect germ cells from injurious substance in the blood ( circulating immunoglobulin's that may affect

spermatogenesis spermatogenesis B) prevents antigenic prouct of germ cell division from entering the circulation .B) prevents antigenic prouct of germ cell division from entering the circulation .

5- contain aromatse enzymes5- contain aromatse enzymes responsible for conversion of androgens to estrogens . responsible for conversion of androgens to estrogens .

6- receptors for FSH6- receptors for FSH are present only in setoli cells . are present only in setoli cells .

SpermatozoaSpermatozoa Each sperm is motile cell composed of a head, Each sperm is motile cell composed of a head,

body and tail body and tail

1- The head :1- The head : consists of nucleus formed consists of nucleus formed of chromosomal material (DNA), then of chromosomal material (DNA), then cytoplasm and cell membrane .cytoplasm and cell membrane .Acrosome : Thick cap that covers the Acrosome : Thick cap that covers the anterior 2/3 of the head ,formed mainly from anterior 2/3 of the head ,formed mainly from the golgi apparatus .Acrosome contain many the golgi apparatus .Acrosome contain many enzymes including hyaluronidase and enzymes including hyaluronidase and protolytic enzymes that help the sperm to protolytic enzymes that help the sperm to penetrate the fertilized ovum .penetrate the fertilized ovum .

2-The body2-The body : collection of mitochondria : collection of mitochondria surrounding the proximal part of the tail .surrounding the proximal part of the tail .

3-The tail (Flagellum):3-The tail (Flagellum): The motility of The motility of the sperm is produced by movement of its the sperm is produced by movement of its tail. ATP synthesized by the mitochondria tail. ATP synthesized by the mitochondria supplies the energy required for flagellar supplies the energy required for flagellar movement. movement.

Capacitation of the Capacitation of the spermatozoa :spermatozoa :Contact of sperm with fluids in the female Contact of sperm with fluids in the female genital tract from 1-10 hoursgenital tract from 1-10 hours

TestosteroneTestosterone The tests secrete several male sex hormones ,which collectively called The tests secrete several male sex hormones ,which collectively called

Androgens Androgens ,including,including; ; 1- testosterone ,more abundant1- testosterone ,more abundant2- Dihydrotestosterone 2- Dihydrotestosterone 3- Andrstenedione 3- Andrstenedione Testosterone is formed by the interstitial cells of leydige .it is a steroid hormone Testosterone is formed by the interstitial cells of leydige .it is a steroid hormone

Transport of testosteroneTransport of testosterone

65% of testosterone is bound to beta globulin called gonadal steroid binding 65% of testosterone is bound to beta globulin called gonadal steroid binding globulin = GBGglobulin = GBG33% Loosely bound to albumin .33% Loosely bound to albumin .

Actions of testosterone :Actions of testosterone :1) 1) Primary sex organs (TESTS);Primary sex organs (TESTS);Testosterone and FSH are important for spermatogenesis Testosterone and FSH are important for spermatogenesis

2)Secondary sex organs;2)Secondary sex organs;It is essential for development ,growth and maintenance of male secondary It is essential for development ,growth and maintenance of male secondary sex organs i.e epididymis, vas deference ,seminal vesicle ,prostate, sex organs i.e epididymis, vas deference ,seminal vesicle ,prostate, bulbouretheral glands ,penis and scrotumbulbouretheral glands ,penis and scrotum . .

Secondary sex charactersSecondary sex characters;;

A) hairA) hair ; ; Body hair is increased but scalp hair is decreased ,hair appearBody hair is increased but scalp hair is decreased ,hair appear on the on the face,face, on the chest , axilla and over the pubis .hereditary baldness appear . Pubic on the chest , axilla and over the pubis .hereditary baldness appear . Pubic hair is triangular toward the umbilicus.hair is triangular toward the umbilicus.

B) skinB) skin :is thickened with excessive thick secretion of sebaceous glands :is thickened with excessive thick secretion of sebaceous glands

C)Voice ;C)Voice ; Larynx enlarge .vocal cord increase in length and thickness ,voice Larynx enlarge .vocal cord increase in length and thickness ,voice become deeper and lower in pitch become deeper and lower in pitch

D)Body configrationD)Body configration ; Shoulder broaden and muscles enlarge . ; Shoulder broaden and muscles enlarge .

E) Behaviour changesE) Behaviour changes : increased libido (Sexual desire ) and male become : increased libido (Sexual desire ) and male become aggressive .aggressive .

General metabolic effects ;General metabolic effects ;Testosterone has protein anabolic effects; Increase protein formation in the target Testosterone has protein anabolic effects; Increase protein formation in the target sex organs ,muscle & bones. This increase ; muscle bulk ,formation of bone matrix sex organs ,muscle & bones. This increase ; muscle bulk ,formation of bone matrix and deposition of calcium salts therefore testosterone is used for the treatment of and deposition of calcium salts therefore testosterone is used for the treatment of osteoporosis in old age .osteoporosis in old age .

Secondary to anabolic actionSecondary to anabolic action ; ; TESTOSTERONE LEADS TO ;TESTOSTERONE LEADS TO ;

Increased rate of growth (Increased rate of growth (GROWTH SPURTS )GROWTH SPURTS ) at a time of puberty but androgens at a time of puberty but androgens terminate growth by causing epiphysial closureterminate growth by causing epiphysial closure

Increased Basal metabolic rate .Increased Basal metabolic rate .

Increase red blood cell count .Increase red blood cell count .

CONTROL OF TESTOSTERONE SECRETIONCONTROL OF TESTOSTERONE SECRETION Testosterone secretion is controlled by LH Testosterone secretion is controlled by LH

(ICSH) secreted by the basophile (ICSH) secreted by the basophile gonadotrophin of the anterior pituitarygonadotrophin of the anterior pituitary

Control of LH secretion ;Control of LH secretion ;1) 1) GONADOTROPHIN –RELEASING GONADOTROPHIN –RELEASING HORMONE (GNRH)HORMONE (GNRH)

Secreted from the hypothalamus and transported to Secreted from the hypothalamus and transported to the anterior pituitary through hypothalamic the anterior pituitary through hypothalamic

hyperphyseal portal circulationhyperphyseal portal circulationStimulate release of gonadotropin LH & FSHStimulate release of gonadotropin LH & FSH

2) testosterone level in plasma (feed back 2) testosterone level in plasma (feed back control )control )

High testosterone level has adirect feed back effect on High testosterone level has adirect feed back effect on ; HYPOTHALAMUS ; HYPOTHALAMUS TO DECREASE SECRETION TO DECREASE SECRETION OF GNRH OF GNRH

THE ANTERIOR PITUITARYTHE ANTERIOR PITUITARY ; to decrease secretion ; to decrease secretion of LH .of LH .

High testosterone levelHigh testosterone level lead to inhibit of GNRH lead to inhibit of GNRH secretion which inhibit FSH & LH Theirfore secretion which inhibit FSH & LH Theirfore injection of testosterone in male for several weeks injection of testosterone in male for several weeks inhibit spermatogenesis .inhibit spermatogenesis .

Low testosterone levelLow testosterone level ; Lack of negative feed back ; Lack of negative feed back effects ,increased gonadotropin secretion effects ,increased gonadotropin secretion increased FSH & LH .this occurs in primary increased FSH & LH .this occurs in primary hypogonadisimhypogonadisim . .

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Abnormalities of testicular functionAbnormalities of testicular function

Male hypogonadismMale hypogonadismHypogonadism of the testes .2 type Hypogonadism of the testes .2 type

Primary ;Primary ; due to testicular failure .gonadotrophin increased both in blood and urine . due to testicular failure .gonadotrophin increased both in blood and urine .

Secondary ;Secondary ; due to failure of pituitary gonadotrophin secretion as in pituitary or hypothalamic due to failure of pituitary gonadotrophin secretion as in pituitary or hypothalamic disease disease

Bilateral castrationBilateral castration

Castration means removal of the testes Castration means removal of the testes Pre puberal castration(before puberty)Pre puberal castration(before puberty)

Permanent sterility due to absence of spermatozoa ,external & internal genital organs infantilePermanent sterility due to absence of spermatozoa ,external & internal genital organs infantile Male sex character don’t develop ,i.e no beard ,soft skin, feminine hair distribution ,weak Male sex character don’t develop ,i.e no beard ,soft skin, feminine hair distribution ,weak

muscle ,sharp voicemuscle ,sharp voice Delays closure of epiphysis leading to overgrowth of long bone (span more than height).Delays closure of epiphysis leading to overgrowth of long bone (span more than height).

Post puberal castration (after puberty)Post puberal castration (after puberty)Gradual decrease of sexual activity Gradual decrease of sexual activity Gradual atrophy of internal genital organs as seminal vesicle prostate ,muscle wasting ,decrease Gradual atrophy of internal genital organs as seminal vesicle prostate ,muscle wasting ,decrease

hair of face hair of face Sexual desire : is depressed ,erection ,ability to copulate is persist but without ejaculation Sexual desire : is depressed ,erection ,ability to copulate is persist but without ejaculation

Male climacteric ,Like female menopauseMale climacteric ,Like female menopause Occurring in old age they have hot flushes sweating nervousness, easy fatigueOccurring in old age they have hot flushes sweating nervousness, easy fatigueIncreased gonadotropin (FSH& LH ) in urine .Increased gonadotropin (FSH& LH ) in urine .

Male hypergonadismMale hypergonadismHyperfunction of the testes rare to occurs Hyperfunction of the testes rare to occurs