Purification and properties of the follicle-stimulating hormone inhibitor obtained from the urine of the bonnet monkey

Abstract

The follicle-stimulating hormone (FSH) inhibitor in monkey urine was purified by selective extraction of the crude extract with acetate buffer, ammonium sulphate precipitation and DEAE-cellulose chromatography. The purified inhibitor was free of luteinizing hormone activity. It behaved as an apparently homogeneous protein. The inhibitor contained about 20% carbohydrate (hexoses, hexosamines, fucose and sialic acid). Thin-layer gel filtration indicated a molecular weight of about 65,000. The inhibitor was labile to heat treatment, exposure to extremes of pH and denaturing agents. The inhibitor effectively neutralized the biological activity of FSH preparations from human, monkey, horse, pig, sheep and rat pituitary glands, pregnant mare serum gonadotrophin and human pituitary urinary gonadotrophin.