THE STUDY ON THE INHIBITORY EFFECT OF ANDROGEN ON THE PITUITARY GONADOTROPIN

Abstract

In order to establish the proper method of administration and adequate dosage of androgen, in cases of primary male hypogonadism, male castrate or male sterility, experimental and clinical investigations were performed.
By the animal experiment using rats, it was proved that inhibitory effect of androgen on the pituitary gonadotropin is very weak. Clinically, alteration of the urinary gonadotropin following respective administration of androgen depot (testosterone heptanate), testosterone propionate, or methyltestosterone was examined and androgenic activity was evaluated at the same time by biochemical procedures.
The results obtained were:
1) By administration of androgen depot 100-250mg per month, the secretion of pituitary gonadotropin was not influenced. But the massive dose (over 400mg) inhibited the secretion.
2) By the use of testosterone propionate 150mg per week, the secretion of pituitary gonadotropin was inhibited, but on cessation it increased more than the level prior to the administration.
3) The continuous administration of methyltestosterone less than 25mg per day which had shown clinical improvement did not cause inhibition of the pituitary gonadotropin secretion.
From the above-mentioned findings the following conclusions were considered.
1) Androgen replacement therapy with adequate dosage for the senescence male complaining of so-called male climacteric symtoms are effective.
2) Androgenic treatment for male sterility applying rebound phenomenon is effective only when the secretion of pituitary gonadotropin is inhibited.
3) Androgen may be effective for the prostatic cancer if an enough dosage to cause inhibition of the secretion of pituitary gonadotropin is given.