Studies on Bovine Pituitary Follicle-Stimulating Hormone1

Abstract

A method is described for preparation of bovine pituitary follicle-stimulating hormone having a relative potency 0.13 times the NIH- FSH-S1 standard. Although at an early stage of chemical purification, the biological purity of this material, as expressed by the FSH/LH ratio, is at least 3 times greater than that of the widely utilized NIH-FSH-S1. Partial purification was achieved by fractionation of a primary hormone concentrate with ammonium sulfate, followed by extraction with chloroform-butanol and isoelectric precipitation of impurities. Fractions having potencies 3 times greater than NIH- FSH-S1 have been prepared in solution by filtration through Sephadex G-100. The potencies of the principal bovine FSH fractions are expressed in terms of a number of commonly employed standard preparations.