Some aspects of synthetic progestins mechanism of action

ABSTRACT

Medroxy progestrone acetate [Depo Provera] could stop ovulation for at least two month in rats by reducing LH in the anterior pituitary and accordingly plasma LH levels. FSH was not affected except at higher dose equivalent to ten times the human dose. Reduction in LH levels resulted in inhibition of delta 5-3 beta -OL steroid dehydrogenase enzyme activity and consequently in serum progesterone level. Sorum estrogen levels were also reduced. Signs of uterine atrophy during drug action were observed. These effects were found to be reversible with one and double the human contraceptive doses. With ten times the dose, these effects seemed to be irreversible