ON THE BIOLOGICAL PROPERTIES OF HIGHLY PURIFIED GONADOTROPIN FROM PREGNANT MARE SERUM

Abstract

The response of hypophysectomized and normal immature [female] rats to the inj. of 4, 12, 24, 30, 36, 60 and 120 R.U. of highly purified equine gonadotrophin was similar to the response of similar amts. of gonadotrophin in untreated pregnant mare serum. In hypophysectomized [female][female] 4 R.U. produced interstitial cell repair with no apparent effect either upon the follicles or indirectly upon the vagina and uterus; 12 R.U. produced interstitial cell repair, follicular development with some luteinization and estrous changes in the uterus and vagina; still larger amts. resulted in more luteinization. The purified extracts, like untreated serum, produced superovulation resulting in superfecundity following breeding of treated immature rats. Comparable amts. of hormone in extracts and untreated serum gave similar responses in normal immature [male] rats. The gonado-trophic activity of mare serum is evidently dependent, not upon a mixture of FSH and LH, but upon a single gonadotrophin. The term "equine gonadotrophin" is suggested for this substance.