Some Effects of Purified Placental Protein (Human) on Lipid and Carbohydrate Metabolism

Abstract

Purified placental protein (human) [PPP(H)], a protein fraction from human placentae, has been reported to react immunologically with antibodies against human growth hormone and to possess somatotropic and lactogenic activities. Parenteral injection of PPP(H) significantly altered a variety of lipid and carbohydrate parameters in a manner qualitatively similar to porcine growth hormone (PGH) in several species of experimental animals. A significant rise in plasma free fatty acid (FFA) concentration was observed in fasted rabbits 6 hr after intramuscular injection of either PGH or PPP(H) (1 or 2 and 25 or 50 mg/kg, respectively). When injected intravenously [10 mg/kg PPP(H)] plasma FFA elevation was similar to that produced by PGH (0.5 mg/kg) in time of onset and duration. In fasting Cercopithecus (African green) monkeys, intramuscular injection of PPP(H) (50 and 100 mg/kg) resulted in marked increases in plasma FFA within 3 hr, and lasting 24 and 12 hr, respectively. Plasma lactescence, associated with hypertriglyceridemia and hyperglycemia, was manifested in rabbits injected subcutaneously with either 75 mg/kg PPP(H) or 4 mg/kg PGH daily for 25 days. In mice, hepatic lipidosis resulted after 7 daily injections of 1.3 or 16 mg PGH or PPP(H), respectively. Hepatic lipid concentration did not differ from control after 14 days of treatment. Subcutaneous injection of PGH or PPP(H) in hypophysectomized adult rats increased myocardial and rectus femoris glycogen concentrations in a dcse-related manner.(Endocrinology79: 709, 1966)