The Location of the Chemoreceptor Controlling Growth Hormone Secretion during Hypoglycemia in Primates

Abstract

Monkeys were prepared with multiple, chronically implanted intracranial cannulae. Such animals when sedated with phencyclidine were found to have persistently low basal plasma growth hormone (GH) concentrations and to secrete GH and cortisol in response to insulininduced hypoglycemia and iv administered 2– deoxy—D—glucose (2DG). Microinjections of 2DG were made into many hypothalamic sites in these animals. Injections into most of the hypothalamus, including the ventro—medial nucleus, and into the third ventricle were without effect upon GH output. Unilateral microinjections of 2DG into the lateral hypothalamic area alongside the mid—part of the ventro—medial nucleus were invariably followed by a sustained rise in plasma GH comparable in magnitude and duration to that provoked by hypoglycemia. It is inferred that the chemoreceptors which control the GH secretory response to hypoglycemia are located in this area. (Endocrinology91: 217, 197