Effects of a growth hormone releasing factor in man.

The effects of the 44-amino acid growth hormone releasing factor (GRF-44) were tested in normal adult men and women. At a dose of 1 microgram/kg, intravenous boluses of GRF-44 stimulated prompt elevations of plasma GH, which in 5 men reached maximum levels of 34 +/- 28 (S.D.) ng/ml, and in 3 women in the mid-follicular phase, 53 +/- 10 ng/ml. The action of GRF was highly selective; there were no changes in plasma PRL, LH, FSH, TSH, or cortisol at this dose level. Side effects, mostly flushing and a sense of warmth of the face and chest, were mild and occurred only in a minority of subjects.