QUANTITATIVE BIO-ASSAY OF CHOBIONIC GONADOTROPHIN WITH THE MALE FROG

Abstract

The male Rana pipiens reacts to chorionic gonadotropin by liberating sperm into the urine. At least 35 I.U. of gonadotropin are necessary to provide a positive response in 75% of these animals, whereas doses to 70 I.U. and above initiate a positive response in 100% of tested animals. The time required for the liberation of sperm is indirectly proportional to the dose of gonadotropin admd. The time response-dose relationship is constant enough to provide a relatively accurate quantitative bio-assay technique which is complemental to the conventional minimal effective dose technique.