Effect of endogenous GH secretion during hyperthermic bath on glucose metabolism and insulin release in man

In healthy male subjects the hyperthermic water bath (40 degrees C for 30 min) induced an increase of growth hormone (GH) level in plasma with the increment higher than 5 ng ml-1. One group of six good GH responders--with the mean increment of 10.9 +/- 1.67 ng ml-1 was given glucose per os immediately after the bath. In other experiment the oral glucose tolerance test (GTT) was performed in six good GH responders (mean increment 16.1 +/- 2.0 ng ml-1) at 90 min after the peak of GH increase. In both experiments the insulin release and glucose tolerance did not differ from the results obtained in the same group in a control isothermic water bath at 30 degrees C. It is concluded that endogenous increase of GH in healthy subjects did not affect the insulin secretion and disappearance of glucose from peripheral blood.