Effect of growth hormone releasing hormone on growth hormone secretion in type 2 (non-insulin-dependent) diabetes mellitus.

Growth hormone levels following an intravenous bolus injection of 1 micrograms/kg body weight growth hormone releasing hormone were measured in 21 non-obese and 26 obese patients with Type 2 (non-insulin-dependent) diabetes mellitus and in 13 control subjects. Growth hormone responses in non-obese Type 2 diabetic patients were not statistically different from control subjects. However, obese Type 2 diabetic patients had significantly decreased growth hormone responses to growth hormone releasing hormone when compared with non-obese Type 2 diabetic patients (p less than 0.02). In 9 Type 2 diabetic patients growth hormone releasing hormone tests were performed both during hyperglycaemia and after metabolic improvement by insulin treatment. Growth hormone responses before and after insulin treatment were not statistically different. Our data demonstrate that growth hormone responses to growth hormone releasing hormone in non-obese Type 2 diabetic patients do not differ significantly from control subjects; obesity blunts growth hormone responses to growth hormone releasing hormone in Type 2 diabetes mellitus; and growth hormone responses following growth hormone releasing hormone administration in Type 2 diabetes mellitus are not influenced by the state of metabolic control.