Bioassay of Pituitary Gonadotropins

Abstract

DURING the course of purification of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from horse pituitary glands¹ the following method was used to determine the degree of separation of FSH and LH at two purification steps. A pH-5 soluble gonadotropic fraction and a purified FSH preparation from the third zone-electrophoresis were compared as to their effect on the increase in the weight of ovaries as a measure of FSH and ventral prostates as a measure of LH in hypophysectomized rats (Holtzman Co., Madison, Wisconsin). A dose-response relationship was developed between the ovarian weights obtained by different doses of the pH-5 soluble fraction. The doses of the FSH fraction from the third zone-electrophoresis were selected so as to induce essentially the same ovarian response as was obtained with various doses of the pH-5 soluble fraction. The average weights of the ventral prostates produced by these doses were used as a measure of the LH content of the two fractions. The results are presented in Fig. 1 and Table 1.