The Acute Insulin Synergistic Activity of Growth Hormone - II) Reversal of Chronic Growth Hormone Effect by Actinomycin D[*]

Abstract

The repetitive administration of growth hormone is capable of abolishing the acute insulin synergistic action of a single G. H. injection. Administration of Actinomycin D, a potent inhibitor of DNA dependent RNA synthesis, along with repetitive G. H. injection allows a return in the ability of an acute G. H. injection to impair insulin degradation and enhance the metabolic action of insulin. In addition, Actinomycin D administration along with chronic G. H. results a continuing sensitivity to exogenous insulin. We therefore postulate that chronic G. H. administration results in the generation of some factor which inhibits the acute insulin synergistic influence of growth hormone. Furthermore, accumulation of that material which impairs early G. H. enhancement of insulin action might account for the insulin antagonistic effect of chronic G. H. administration.

Key words

Chronic GH-Treatment in Rats - Generation of GH-Inhibiting Factor - Insulin Antagonism - Actinomycin D.

1 This work was supported in part by Grant #U-1836 of the Health Research Council of the City of New York and by Grant # GB 525I X of the Division of Biological and Medical Sciences, National Science Foundation, Washington, D. C.

1 This work was supported in part by Grant #U-1836 of the Health Research Council of the City of New York and by Grant # GB 525I X of the Division of Biological and Medical Sciences, National Science Foundation, Washington, D. C.

2 Recipient of a Research and Development Award of the American Diabetes Association.