Abstract
Changes in serum LH and FSH were measured following injection of synthetic tetrapeptide (Glu-Tyr-Arg-Trp-NH2) or synthetic LH-RH into the femoral vein of oophorectomized rats. A considerable secretion of LH occurred after injection of synthetic tetrapeptide although its LH-releasing activity was less prominent than that observed after injection of LH-RH. No appreciable FSH-releasing activity was noted following injection of the tetrapeptide. A significant rise of LH and an observable, but extremely modest, rise of FSH with an indistinct peak were noted after single injection of synthetic LH-RH.
