GONADOTROPINS OF THE SWINE PITUITARY I. VARIOUS BIOLOGICAL EFFECTS OF PURIFIED THYLAKENTRIN (FSH) AND PURE METAKENTRIN (ICSH)

Abstract

SEVERAL RECENT STUDIES from this laboratory offer strong support of the belief (1)that at least two gonadotropins can be isolated from extracts of pituitary glands. Preliminary evidence was obtained from experiments with extracts of hog glands digested by proteolytic enzymes permitting differentiation of gametogenic (‘follicle stimulating’) and interstitial cell-Stimulating effects depending upon the enzyme used and the extent of digestion (2). Physicochemical methods were next employed to separate the gonadotropins from hog pituitary extracts which had not undergone preliminary enzymic hydrolysis (3). The interstitial cell-Stimulating hormone as a pure protein was isolated (4). The gametogenic hormone was separated as a substance with only one apparent biological effect; however, the purest preparations contained small proportions of two contaminating impurities. Work in the University of California (5) likewise led to the isolation of interstitial cell-Stimulating hormone from pituitary glands of another mammal, the sheep.