The exact physiological basis for the suppression of
growth hormone secretion by oral
glucose intake remains unknown, despite the widespread use of the oral
glucose tolerance test in endocrinology. Lack of
growth hormone suppression by
glucose occurs in about a third of patients with
acromegaly, as well as in other disorders. It is currently known that the secretion of
growth hormone is affected by various factors, such as age, gender, body mass index, and the redistribution of adipose tissue. There is also evidence of the impact of
overeating as well as being
overweight on the secretion of
growth hormone. It is known that both of these conditions are associated with
hyperinsulinemia, which determines the possibility of its predominant role in suppressing the secretion of
growth hormone. The purpose of this review is to discuss the accumulated data on the isolated effects of
hyperglycemia and
hyperinsulinemia on
growth hormone secretion, as well as other metabolic regulators and conditions affecting its signaling. Understanding of the pathophysiological basis of these mechanisms is essential for further research of the role of
glucose and
insulin in the metabolic regulation of
growth hormone secretion. However, the studies in animal models are complicated by interspecific differences in the response of
growth hormone to glucose loading, and the only possible available model in healthy people may be the hyperinsulinemic euglycemic clamp.