The response of growth hormone and prolactin to oral diazepam in diabetics.

We studied 8 insulin dependent stable young diabetics with a mean age of 20 yr. Each patient received 10 mg of diazepam orally after with drawing the baseline blood sample. Subsequent samples were obtained at 30 min intervals for 150 min. The oral administration of diazepam resulted in a significant increase in serum GH concentration from a baseline value of 5.3 +/- 1.2 ng/ml (mean +/- SE) at 0 point to a peak response of 16.5 +/- 5.9 ng/ml at 60 min (p less than 0.001). The plasma glucose concentration remained in the range of 200-267 mg/dl and did not change significantly during the entire testing period indicating that diazepam stimulates GH release in diabetics despite endogenous hyperglycemia. Eight normal subjects were also studied in an identical fashion. Although the mean baseline serum GH concentration in these normal subjects was significantly lower than that observed in the diabetics, (1.3 +/- 0.4 vs 5.3 +/- 1.2 ng/ml, p less than 0.05), the peak response did not differ significantly between the two groups (10.7 +/- 2.6 vs 16.5 +/- 5.9 ng/ml; NS). The baseline concentration of serum prolactin was similar in the diabetic and nondiabetic groups and the administration of diazepam resulted in no significant changes in both groups. Diazepam may be a useful agent in testing for GH reserve in normal subjects as well as in stable insulin dependent young diabetics.