2. Male sex hormones
Androgens or androgenic hormones
Testosterone, androsterone, dehydroepiandr
osterone
Androsterone is the first to be isolated
The main commercial source of androgens:
urine of male , female and testicular extract
Androgens also produced in A. Cortex
Testosterone is the most potent
4. Metabolism
Liver
Principal metabolites: 17-ketosteroids
17-KS give colour reactions such as
Zimmermann (m-dinitrobenzene) and Pincus
( antimony trichloride) reactions
17-KS are of 2 types
1. neutral and acidic
5. Reactions involved in androgen
metabolism
1. conversion of C17 –OH group to the keto group
2. reduction of 4,5 double bond
3. reduction of ketonic group at C3
4. conjugation with glucuronic acid or sulphuric acid
Most imp 17-KS isolated from urine are
androsterone, etiocholanolone, dehydroepiandroste
rone, epiandrosterone.
The amt of 17-KS increases with age and in
pregnancy
6. Metabolism
Abnormally high 17-KS are found: in increased
adrenocortical function, increased interstitial cell
function
Slight increase of 17-KS found in: acute
illness, starvation, anoxia, physical or mental
stain, exposure to cold and post- operative state
Low values : hepatic diseases, chronic
illness, anemia, malnutrition, malignancy decreased
amt of gonadotropic and adrenocorticotropic
hormones
7. Functions
Testosterone is the most active
Testosterone > androsterone > dehydroepiandrosterone >
epiandrosterone
Promotes growth and function of the male accessory sex
organs, viz prostate gland, seminal vesicles, Cowper’s glands and
penis
Development of 20 sex characteristics viz texture of
skin, distribution of hair, voice etc
Promotes protein syn in accessory organs
Increase the activity of glycolytic enzymes
Decrease the activity of alk.phosphatase, glutamic
dehydrogenase & hepatic arginine synthetase
8. Functions
Increase the rate of synthesis of FAs
Increase the rate of production of fructose by
the seminal vesicles
Increase the rate of synthesis of citrate
Increase respiration ( O2 consumption and
CO2 production ) of the seminal vesicles and
of the prostateincrease the tubular
reabsorption of citrate, Na, K, Cl-, SO4
2-, PO4
3-
9. Hormones of Corpus luteum
hormones
Pregnancy hormones / Gestogens
Progesterone is the most imp of this group
Secreted by corpus luteum part of ovary
Degraded to inactive pregnanediol
Main source : corpus luteum
Also found in placenta, pregnancy urine, and
adrenal cortex
10. Biosynthesis
Acetate
Corpus luteum , adrenal corted, testes and placenta
It is secreted a day or two earlier, or on the day of
ovulation from the corpus luteum
Its secretion is stimulated by prolactin
It is bound in plasma to the corticosteroid-binding
globulin (CBG)
The principal excretory product of progesterone is
pregnanediol formed by the reduction of
Progesterone
11. Functions
In conjunction with estrogenic hormones, it prepares
the uterine mucosa for the reception of fertilized
ovum
Maintains the conditions for its further growth
Exhibits antiovulatory property ( used as oral
contraceptive)
In conjuction with estrogen, progesterone causes
development of the alveolar system of the breast
Increases the BMR
Effects electrolyte and water metabolism
12. Relaxin
Another hormone from corpus
luteum, placenta and uterus
Found in blood of pregnants
Chemically it is PP (mol.wt 90,000)
Mammary development in rats
Anti-diuretic effect in rats