reproductive hormones cc2 midterm

sex hormones (male and female gonads)

are synthesized from cholesterol and secreted throughout a person's lifetime at different levels

hypothalamus and pituitary gland

_________________ and __________________ control production of sperm and sex hormones in the testes

gonadotrophin releasing hormone

male reproductive system: at puberty, hypothalamus secretes ___________________

follicle stimulating hormone and luteinizing hormone

GnRH activates anterior pituitary to release ______________________ and _________________

Luteinizing hormone (LH)

stimulates the development of the testes

follicle stimulating hormone (FSH)

activates testes' sperm forming cells

luteinizing hormone

testosterone inhibits ______________________ production by the pituitary gland by deactivating hypothalamus

negative feedback mechanism

once high levels of testosterone are detected by the hypothalamus, a __________________________ is activated

testosterone

most potent male androgen

leydig cells

testosterone: synthesizd by the _____________ of the testis

genitalia

functions of the testosterone (in fetus)

development of male internal and external ________________

growth development

functions of the testosterone (in fetus)

_________________ (acting with other hormones, stimulates e.g. protein anabolism)

behavioural effects

functions of the testosterone (in fetus)

______________________ during development

1. spermatogenesis

2. protein anabolism

3. puberal growth spurt

4. feedback regulation

5. behavioural effects (aggression and competitiveness)

functions of the testosterone (in adult):

1. male genitalia

2. secondary accessory sex glands

3. secondary sex characteristics

functions of the testosterone (in adults) growth and development of:

8 am and 8 pm

circadian pattern (peak at ____________ and lowest at ____________

1. pretesticular

2. testicular

3. post-testicular

infertility may be

pretesticular infertility

due to hypothalamic and pituitary lesions

normal or decreased

in pretesticular infertility:

testosterone, FSH and LH may be

testicular infertility (primary gonadism)

may be congenital (cryptochidism, klinefelter's syndrome and 5-alpha-reductase deficiency or acquired (varicocele, tumor, orchitis)

decreased and increased

primary intertility: _________ testosterone and ____________ LH or FSH

post testicular infertility

due to disorders of sperm transport and function

normal

testosterone, LH and GSH are _________________

crytochidism

(from the greek kryptos meaning hidden and orchis meaning testis) refers to absence of a testis from the scrotum

klinefelter's syndrome

a genetic condition affecting 1 in 650 men

klinefelter's syndrome

due to presence of an extra X chromosome (47XXY)

klinefelter's syndrome

the most common cause of androgen deficiency

androgen deficiency

impaired testorone production

azoospermia

impaired spermatogenesis

testosterone treatment

klinefelter's syndrome men will benefit from life long ________________

1. small firm testis

2. reduced facial body and pubic hair

3.gynaecomastia

4. feminine fat distribution

5. taller tha average

6. poor muscle development

klinefelter's syndome characteristics

1. semen analysis

2. LH

3. FSH

4. testosterone

test for infertility

testicular feminization syndrome

the most severe form of androgen resistance syndrome -> lack of testosterone action in the target tissue

testicular feminization syndrome

physical development-> female phenotype-> fully developed breast and female distribution of fat and hair

testicular feminization syndrome

no response or response to exogeneous testosterone

normal testosterone, increased LH and FSH

lab test of testicular feminization syndrome

sertoli cell only syndrome

characterized by a lack of germ cells

1. small testis

2. normal testosterone

3. elevated FSH

4. azoospermia

sertoli cell only syndrome: men present with:

testicular biopsy

sertoli cell only confirmatory/ diagnosis test:

myotonic dystrophy

inherited in autosomal dominant fashion

1. hyponadism

2. frontal balding

3. diabetes

4. muscular weakness

5. atrophy

6. dystonia

myotonic dystrophy presents with

normally

myotonic dystrophy puberty progresses

testicular injury and infection

mumps orchitis-> most frequemt extrasalivary manifestation of the infection

unilateral

mumps epididyma-orchitis usually

4 to 6 days ff

most cases occurs within _____________ of parotitis

kallman's syndrpme

inherited x-linked recessive trait that manifests as hypogonados, during puberty

1. anosmia

2. midline defects (cleft palate and lip)

defects of kallman's syndrome

kallman's syndrome

most common form hypogonadotropic hypogonadism due to deficiency of Gnrh

5A-reductase deficiency

rare cause of andorgen sensitivity

5A-reductase deficiency

results in decreased DHT concentrations

5A reductase

female internal genitalia are absent and the male internal genitalia are well developed

DHT

essential for the development of the prostate and external genitalia during embryonic virtilization

estrogen and progesterone

sex hormones of female reproductive system

estrogen

arises from structural alteration of the testosterone molecule

1. promotion of breast development

2. maturation of external genitalia

3. deposition of body fat

4. secondary charactersitic of female

estrogen important for

1. function in uterine growth

2. menstrual cycle regulation

3. maintaenance of pregnancy

in conjunction with progesterone:

endometrium

deficiency of estrogen results in irregular and incomplete development of the ______________

menopause

estrogen is not produced by ovaries after ________________

estrone

most abundant estrogen in post menopausal women

estradiol

most potent estrogen; major estrogen

estradiol

most abundant in pre menopausal women

E1 and E2 (FSH)

estradiol precursor of both _________ and ___________, serve as negative feedback to ___________

estradiol

used to assess ovarian function

estriol

metabolite of estradiol

maternal urine

estriol: estrogen found in ____________

placenta (pregnancy)

major estrogen secreted by ____________ during _____________

down syndrome (AFP and HCG

estriol used as a marker for ______________ (together with _________ and __________)

progesterone

produced mainly by the granulose cells of the corpus luteum

progesterone

prime secretory product of the ovary

progesterone (ovulation)

the single best hormone to determine ______________

pregnancy and lactation

progesterone

prepare the uterus for _______________ and the breast for ______________

progesterone

evaluation of infertility

embryo implantation

deficiency results in failure of ___________

androgen

ovaries also produce

1. hirutism

2. defeminisation

3. virilization

excess production of ovarian androgen can lead to

2nd trimester

HCG, AFP, unconjugated estriol

neural tube defects and down syndrome are determined during early ___________ by screening maternal serum for levels of ___________, ____________ and _____________

inhibin A (the 4th down syndrome)

a reproductive hormone which inhibits FSH activity; the _______________________

karyotyping and FISH typing

test down syndrome using amniotic fluid as specimen