Effects of ambient glycaemic state on growth hormone responsiveness in insulin-dependent diabetes

Abstract

Objective: We wished to examine the effects of ambient glycaemia on hypothalamic somatostatinergic tone in insulin-dependent diabetes mellitus.

Design: After 6-hour periods of either euglycaemia (5 mmol/l) or hyperglycaemia (15 mmol/l), exercise-induced GH secretion was measured.

Patients: Seven insulin dependent diabetics with no evidence of complications were recruited.

Results: There was no significant difference between basal GH levels during euglycaemia and hyperglycaemia (5.50 vs 5.53 mU/l). Nor was there a significant difference when mean delta GH levels (33.9 vs 27.4 mU/l) or mean area under GH curve (2331 vs 4038 mU min/l) during euglycaemia or hyperglycaemia were compared.

Conclusions: We find no evidence therefore to support short-term effects of ambient glucose concentration on GH responsiveness, and by inference no direct effect of short-term changes in glycaemic control on hypothalamic release of somatostatin in the aetiology of GH hypersecretion in insulin-dependent diabetes mellitus.