Effect of Anterior Pituitary Growth Hormone on Synthesis of Acetoacetate by Surviving Slices of Rat Liver

Abstract

A stuay was made of the effect of pretreatment with anterior pituitary growth hormone (GH) on the synthesis of acetoacetate by surviving slices of rat liver. It was found that the liver slices from the GH animals produced significantly greater quantities of acetoacetate than did slices from the isocalorically fed controls. There was also noted a marked and sudden depletion of liver glycogen as a result of the GH admn. These findings were repeatedly seen in fed rats receiving GH injns. over several days, or 2 hrs. after a single GH injn. in 18- to 24-hour fasted rats. Further studies on the "single injection" rats showed that in 2 hrs. after GH admn. there was a hypoglycemia, ketonemia and increased liver lipid content. These later findings were in agreement with similar observations of others. It was suggested that the accelerated fat catabolism induced by GH treatment might well be secondary to the depletion of liver glycogen, a sequence of events similar to those seen in other states where stores of liver glycogen are depleted. Such an explanation of the observed facts would place the biochemical site of action of GH somewhere in the chain of reactions of glycogenolysis. It was further suggested that the ketosis and fatty liver of uncontrolled diabetes might be the result of an aberration in the normal synergism between GH and insulin as they regulate the synthesis of new protein for tissue growth.