Gonadal Function Flashcards
Reproductive endocrinology is made up of the hormones of the ______________ axis and the _________
These hormones are crucial for proper reproductive function.
hypothalamo-pituitary –gonadal
adrenal glands.
Hormones
_________________
——————-
____________
___________________
Gonadotropin-releasing hormone (GnRH)
Leutinizing hormone (LH)
Follicle stimulating hormone (FSH)
Sex steroids (oestrogens, progesterone, and androgens)
Male Reproductive Physiology
The function of the testes is to synthesize ________________
Sertoli cells in the ________ of the ________ play a cruicial role in ________________ and secrete ________ which inhibits _________________
both spermatozoa and androgens
seminiferous tubules
testes ;sperm maturation
inhibin ; pituitary secretion of FSH.
Male Reproductive Physiology
Surrounding the seminiferous tubules are the _______ of ________ which produce testicluar ______ and necessary for sperm maturation, and secondary sex characteristics.
interstitial cells of Leydig
androgens
Male Reproductive Physiology
GnRH is a ____peptide synthesized in the ________ and transported to the ________ where it stimulates release of ____________
deca; hypothalamus
anterior pituitary
both FSH and LH.
Male Reproductive Physiology
LH acts on ________ to synthesize ______.
FSH acts on ________ to stimulate _______ and the synthesis and release of ______.
Leydig cells ; testosterone.
Sertoli cells ; gametogenesis
inhibin.
Male Reproductive Physiology
Sex steroids and inhibin provide the negative feed back control of _______________ secretion respectively.
LH and FSH
Androgens
Androgens cause ________ of the genital tract and maintenance of the male secondary sex characteristics
Muscle bulk, deepening of voice
Bone mass
Libido and sexual performance in men
masculinization
__________ is the main androgen secreted by the ____ cells in men
Women produce _____% as much as men
Testosterone
leydig
5-10
Other androgens secreted by the adrenal glands
List 4
Dehydroepiandrosterone (DHEA)
Dehydroepiandrosterone sulphate (DHEA – S)
Androstenedione
Androstenediol
Other androgens secreted by the gonads
List 2
Dehydroepiandrosterone (DHEA)
Androstenedione
Biochemistry and Physiology
The synthesis of androgens begins with formation of __________ from _______
pregnenolone from cholesterol
Biochemistry and Physiology
Testosterone circulates free or bound to plasma proteins like ____________________ and ____________.
sex hormone binding globulin and albumin
SHBG binds ________________________. In either sex
increased SHBG ______eases oestrogen dependent effects and decreased SHBG ases androgen dependent effects.
both testosterone in males and oestradiol in females
incr
Metabolism of testosterone
Testosterone : precursor for formation of ______(___________) and _______.
Both are active metabolites and are converted by _______ and _______ respectively.
DHT (dihydrotestosterone)
oestradiol
5α reductase; aromatase
Metabolism of testosterone
Aromatisation occurs in _______ tissue of both sexes because of the high concentration of _ _______ in adipose tissue.
adipose
aromatase
DHT is formed in _____ target tissues eg _______ and _____
androgen
skin and prostate.
Metabolism of testosterone
Excretory products of these androgens constitute a group of androgens known as __________ – ketosteroids , 90% of which is excreted in ____.
‘17 - ketosteroids
urine.
Male reproductive development
Fetus: has both _________ (female) and _________ (male) reproductive tracts.
The _________ duct differentiates into the fallopian tubes, uterus, upper vagina and female reproductive tract.
The ________ differentiates into vas deferens, epididymis, seminal vesicles and male reproductive tract.
Mullerian duct (female)
Wolffian duct (male)
Mullerian duct
Wolffian duct
Male reproductive tract
In males, _______ maintains the _______ duct and ________ of the urogenital sinus and external genitalia.
________________ is responsible for repression of the Mullerian duct.
testosterone
Wolffian; virilisation
Mullerian Inhibiting Substance (MIS)
Post natal development: Male reproductive system
After birth, concentration of testosterone increases and remains elevated for _______ then falls to baseline by ______ (< 1nmol/L). I
t remains low although (lower or higher?) in boys than girls till _______.
3 months
1 year
Higher ; puberty
At birth concentration of testosterone is only SLIGHTLY higher in boys than girls.
T/F
T
Puberty: Male Reproductive System
Hypothalamopituitary system becomes (more or less?) sensitive to feedback inhibition by circulating androgens, resulting in (lower or higher?) androgen secretion.
Less
Higher
Puberty: Male Reproductive System
By 6/7 yrs of age, ______,_______, and ________ begin to increase. Puberty is associated with (diurnal or nocturnal?) surges of ____ and to a lesser extent ____.
androstenedione, DHEA and DHEA-S
nocturnal
LH; FSH
Andropause
The ______ process leads to physiological lowering of androgens in men ____ yrs and above.
Symptoms include:
- ____eased well being
- ____eased energy levels
- ____eased sexual function
aging; 50
decr; decr; decr
Andropause
Unlike menopause, andropause does not result in _________________. The process is (more or less?) gradual, progressing over several decades.
absolute loss of gonadal function
More
Disorders of male sex hormones
Deficiency in sperm production and decreased testosterone secretion is known as __________. (Low sperm count)
hypogonadism
Disorders of male sex hormones
They can be PRIMARY DISORDERS affecting the ____ or ____gonadotrophic ____gonadism.((high or low?) FSH/LH).
Or due to a defect in the ______ or SECONDARY DISORDERS or ____gonadotrophic ____gonadism.
testes; hyper; hypo
.(High FSH/LH).
hypothalamus; hypo; hypo
Disorders of male sex hormones
In hypogonadotrophic hypogonadism _____________ may be absent, or ______ may be absent.
both FSH and LH
only LH
Disorders of male sex hormones
Other male reproductive abnormalities include defects in androgen action,
__________
____________
impotence
gynaecomastia.
Causes of primary hypogonadism
Congenital defects – _______ syndrome or testicular _______
Acquired defects like testicular infections eg ______, trauma, _______ or _______ drugs
Klinefelter’s syndrome or testicular agenesis
mumps, trauma, irradiation or cytotoxic drugs
Causes of secondary hypogonadism
_________________
Hypothalamic disorders such as _______ syndrome
Pituitary tumours
Kallman’s
Causes of secondary hypogonadism
Kallman’s syndrome – decreased ______ during _____________ _
It is characterized by ________ and ______ in male or female patients, ____x more common in men. It is a congenital defect with several genetic causes.
GnRH
embryonic development
hypogonadism and anosmia
5x
Female reproductive physiology
Consists of vagina, uterus, fallopian tubes and ovaries.
Ovaries are located on either side of ______ near ___________.
They produce _____ and secrete sex hormones ______ and _______
uterus ; fallopian tubes.
ova ;progesterone and oestrogen.
Female reproductive physiology
Every healthy female neonate has _____ primordial follicles, each containing and immature ovum of which ________ follicles will reach maturity.
400,000
300 to 400
Female reproductive physiology
A ___________ is produced during each normal menstrual cycle at day ____.
During ovulation the mature follicle _____ releasing the ______ into the _____ near the ___________.
single mature follicle; 14
ruptures; oocyte; space ; fallopian tube.
After ovulation, granulosa and theca cells of the follicle become the corpus luteum. These luteal cells produce oestrogen and progesterone.
If fertilization and pregnancy occur, the corpus luteum persists and continues to produce oestrogen and progesterone.
Female reproductive physiology
After ovulation, ________ and _______ cells of the follicle become the _________.
These _____ cells produce oestrogen and progesterone.
If fertilization and pregnancy occur, the ______ persists and continues to produce oestrogen and progesterone.
granulosa and theca
corpus luteum
luteal
Female physiology
If pregnancy does not occur, corpus luteum ______ and is replaced by _______
regresses; scar tissue.
Female physiology
Fallopian tubes arise from the _____, extend towards the ______.
They convey the _____ __ward from the ________ and provide site for _______ of oocyte.
Fertilized egg is transported _____ along the ________ to the _______
Uterus ; ovaries
sperm; up
uterine cavity ; fertilization
Back; fallopian tubes
uterine cavity.
Uterine cavity is lined by _______ which undergoes___ changes in preparation for implantation and pregnancy.
During the _____ phase, endometrial lining increases in thickness and vascularity.
endometrium; cyclical
luteal
Role of the hypothalamopituitary axis
In adult women, a tightly coordinated feedback system exists between ________,________, and ______ to cause menstruation.
hypothalamus, anterior pituitary and ovaries
Role of the hypothalamopituitary axis
FSH stimulates ___________
LH stimulates ________ and ______ secretion from developing corpus luteum.
follicular growth
ovulation; progesterone
Oestrogens
Oestrogens are sex hormones responsible for development and maintenance of female sex organs and female secondary sex characteristics.
T/F
T
Oestrogens
Oestrogen and progesterone regulate the _____ cycle, _____ and ______ growth and _______ pregnancy.
menstrual
breast and uterine
maintain
Oestrogens
Oestrogens affect _______ homeostasis, bone ___, _____eases linear bone growth and results in _______
calcium
mass; incr
epiphyseal closure.
Oestrogens
Oestrogen depletion is associated with loss of _______ content, _____ease in stress fractures, post menopausal ________.
bone mineral
incr
osteoporosis
Oestrogen
Secreted in adult women by ________ and _______ and during pregnancy by the ______.
The ______ gland and ______ also secrete minute quantities of oestrogens.
ovarian follicles and corpus luteum
placenta ; adrenal gland
testes
____________ is the most important oestrogen.
Oestradiol
Progesterone like oestrogens is a female sex hormone.
It is secreted from _______ through ________ just like in the ________.
cholesterol
pregnonolone
adrenal cortex.
Disorders of female gonadal function
__________
__________
________ ,_______, and ————
Hirsutism
Virilism
Subfertility, amenorrhoea and oligomenorrhoea
Hirsuitism
_____eased body hair with ____ pattern distribution.
Genetic in origin and (benign or malignant ?) in majority of cases. (present in some Nigerian tribes)
Incr
male
Hirsuitism
The commonest pathological cause is _____________ syndrome.
It is important to exclude this diagnosis when investigating hirsute women.
polycystic ovarian
Virilism
Although (common or uncommon?), is a sign of serious disease.
Testosterone concentrations are markedly ________ in the virilised patient.
uncommon
elevated
Virilism
Symptoms include ______ pattern hair distribution, ______ of the voice and breast _______.
Tumours of the _____ or the ________ are the likely cause.
male
deepening
atrophy
ovary; adrenal gland
Subfertility, amenorrhea and oligomenorrhea
Subfertility is defined as _______ of a couple to ______________________.
A full clinical history will give information about previous pregnancies, contraception, serious illnesses, radiotherapy, cytotoxic drugs, smoking, drug usage, sex transmitted diseases, frequency of intercourse.
failure
conceive after one year of regular, unprotected intercourse
Subfertility, amenorrhea and oligomenorrhea
Physical examination, hypothalamopituitary disorders, thyroid disorders, Cushing’s syndrome, galactorrhoea, hirsutism.
In ________ analysis should detail volume, sperm density, motility and presence of abnormal spermatozoa.
male semen
Subfertility, amenorrhea and oligomenorrhea
Endocrine investigations of the infertile woman.
Serum progesterone in the middle of the ______ phase or day ____ progesterone should be analysed.
If > ____nmol/L, then patient is ovulating.
If <____nmol/L, then patient is not ovulating.
luteal; 21
30; 10
Subfertility, amenorrhea and oligomenorrhea
For women with irregular menses, measurement of _______ and ________(19- 100 IU/L) may detect ________ failure or __________ disease.
Measurement of ______ and _______ are also important.
oestrodiol and FSH/LH
primary ovarian
polycystic ovarian
prolactin and androgens
Causes of infertility in women
______________ failure
Hyper _________
_________________ disease
_________ syndrome
_____gonadotrophic _____gonadism
Primary ovarian failure Hyperprolactinemia
Polycystic ovarian disease Cushing’s syndrome Hypogonadotrophic hypogonadism
Endocrine investigations in the subfertile man
In a man with ________ analysis no endocrine investigations are needed.
In the hypogonadal male, _____ and _________ should be measured first.
normal sperm
testosterone and gonadotrophins (FSH/LH)
Causes of subfertility in the male
Primary testicular failure
___________ ———- disease (_______ syndrome)
____________ is a rare cause of infertility in the male.
Primary testicular failure
Hypothalamic pituitary disease (Kallman’s syndrome)
Hyperprolactinemia is a rare cause of infertility in the male.
Causes of subfertility in the male
In both men and women a serum FSH concentration greater than ____ U/L indicates ________ ———- ———
23
primary gonadal failure.
Tests in Pregnancy
Specific ______ changes
Secondary _______ changes
_________ monitoring
______ monitoring
Metabolic effects of ________
hormonal
metabolic
Maternal
Fetal; oral contraceptives
