INTERSTITIAL CELL STIMULATING HORMONE. II. METHOD OF PREPARATION AND SOME PHYSICO-CHEMICAL STUDIES1¹

Abstract

ARECENT PUBLICATION (i) from this laboratory described a chemical procedure to separate two gonadotropic fractions from sheep pituitary: the follicle L. stimulating hormone (FSH) andthe interstitial cell stimulating hormone (ICSH). By modification of this method it has now been possible to secure the ICSH in a homogeneous state as judged by electrophoresis experiments. The biological properties of the preparation have been studied in detail and results appeared in Paper I(2).The method of purification and some of the physicochemical properties of the product are presented here. The method of purification is given below; all steps were carried out at 4 to 6°C. (a) The 40% alcohol extract (1) of acetone-dried sheep pituitaries was used as the starting material. The extract was precipitated with alcohol and dried with ab solute alcohol and ether.