FEMALE SEX HORMONES
Steroids are the chemical compounds in which the structural formula is composed of peculiar four membered rings namely A,B,C,and D resumbles that of a compound known as cyclo pentano perhydro phenantherene
In our body all the male and female sex hormones are produced from cholesterol which is a steroid and hence all of them have the steroid structure in their molecules.Among these steroids body can convert one from other as per the need very easily by simple sructural modification.The female sex hormones are all seroids with an aromated phenolic A ring.Hence aromatization of a male sex hormone (Androstenedione) at the A ring will result in the conversion to female sex hormone (Estradiol,the main estrogen in our body) by our body out side ovary.
Our body is secreting in the ovary three female sex hormones namely Estradiol,Estrone,and Estriol.Out of these estradiol comprises the major part.
Esradiol is the main estrogen secreted by our body in the ovary in equillibrium with estrone.Both estradiol and estrone are finally convered to estriol before excretion.
For oral ingetion as estradiol is 100% deactivated by liver on first pass,to prevent this there are esterified semisynthetic estradiols are available for oral contraceptive use.They are Ethinyl estradiol,Mestranol
For intra muscular injections semisynthetic esters like estradiol cypionate and estradiol valerate are highly active as these esters are slowly released from the muscles to give prolonged contraceptive actions
There are nonsteroidal estrogens are available such as diethyl stilbestrol,dienestrol,chlorotrianisene.These non steroidal hormones are nowadays less atractive in use.
Pharmacological actions of Female sex hormones
The specificity of estrogen actions are at the estrogen receptors on estrogen sensitive organ tissues such as vagina,uterus,mammary glands,anterior pituitary and hypothalamus.Estrogen receptors are all nuclear receptors and hence when estrogen bind to the receptor it become a complex with it and enter into the cell and attach with the DNA of the nucleous and exhibit its actions like anabolism or catabolism or enzyme synthesis.One best example is estrogen act on bone receptors and inhibit bone resorption and stimulate new bone formation.It act on kidneys and increase the production of an enzyme,hydroxylase which convert vitamin D to D-3.
On lipid metabolism estrogens slightly increase triglyceride and HDL levels but decrease LDL and total cholesterol.
Uses
1.As contraceptives (combined with progesterone)
2.Treatment of menopausal syndromes such as:-
a.Vasomotor disorders.
b.Urogenital atrophy
c.Psychological disorders
3.Acne
4.Osteoporosis both senile and postmenopausal
5.Prostate cancer
Toxicity
1.GI distress like nausea,vomiting anorexia and diarrhea.
2.Cardiovascular effects like high blood pressure,thrombo embolism,stroke amd heart attack.
3.Fluid retension
4.Hypertriglyceridemia
5.Endomerial (Uterine) Cancer on prolonged use only
6.Liver cancer on prolonged use only
For intra muscular injections semisynthetic esters like estradiol cypionate and estradiol valerate are highly active as these esters are slowly released from the muscles to give prolonged contraceptive actions
There are nonsteroidal estrogens are available such as diethyl stilbestrol,dienestrol,chlorotrianisene.These non steroidal hormones are nowadays less atractive in use.
Pharmacological actions of Female sex hormones
The specificity of estrogen actions are at the estrogen receptors on estrogen sensitive organ tissues such as vagina,uterus,mammary glands,anterior pituitary and hypothalamus.Estrogen receptors are all nuclear receptors and hence when estrogen bind to the receptor it become a complex with it and enter into the cell and attach with the DNA of the nucleous and exhibit its actions like anabolism or catabolism or enzyme synthesis.One best example is estrogen act on bone receptors and inhibit bone resorption and stimulate new bone formation.It act on kidneys and increase the production of an enzyme,hydroxylase which convert vitamin D to D-3.
On lipid metabolism estrogens slightly increase triglyceride and HDL levels but decrease LDL and total cholesterol.
Uses
1.As contraceptives (combined with progesterone)
2.Treatment of menopausal syndromes such as:-
a.Vasomotor disorders.
b.Urogenital atrophy
c.Psychological disorders
3.Acne
4.Osteoporosis both senile and postmenopausal
5.Prostate cancer
Toxicity
1.GI distress like nausea,vomiting anorexia and diarrhea.
2.Cardiovascular effects like high blood pressure,thrombo embolism,stroke amd heart attack.
3.Fluid retension
4.Hypertriglyceridemia
5.Endomerial (Uterine) Cancer on prolonged use only
6.Liver cancer on prolonged use only
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