STARCH-GEL ELECTROPHORESIS OF MOUSE PITUITARY GONADOTROPHINS

Abstract

SUMMARY Extracts of mouse pituitary glands, prepared by homogenization and high-speed centrifugation, were separated into 16–17 fractions by preparative electrophoresis in starch gel, from which the proteins were then recovered by an electrophoretic method. Follicle-stimulating hormone (FSH), assayed by the uterine-weight augmentation method in the hypophysectomized mouse, was confined to 2–3 adjacent portions of the gel 1 cm. wide. Luteinizing hormone (LH) assayed by the rat ovarian ascorbic-acid depletion method was recovered from three discrete regions of the gel, well separated from FSH. The most active LH fraction was of slower mobility than the FSH. Assay for 'total' gonadotrophin, using normal mouse uterine weights, disclosed active material of slow mobility, separated from the FSH fractions. A series of experiments devoted to assays of FSH separated electrophoretically from pooled mouse pituitary glands demonstrated variations in pituitary content and concentration of FSH related to sex, age, pregnancy, lactation, dietary changes and light exposure which were consistent with results of previous studies of the mouse and of the rat.