Hormonal effects and metabolic clearance rate of the enkephalin analogue DAMME in man.

The enkephalin analogue DAMME (0.25 mg) and normal saline were administered by slow intravenous injection to six normal male subjects in a double-blind crossover study. Plasma DAMME concentrations were measured by a specific radioimmunoassay. A significant rise in plasma growth hormone and prolactin and a significant fall in plasma corticotrophin and cortisol concentrations were observed. The fall in pancreatic polypeptide concentration just failed to reach significance. No significant changes were observed in insulin, glucagon, glucose, adrenaline and noradrenaline. Serum concentrations of DAMME were initially high (greater than 6.7 nmol/1) corresponding with the observed maximum plasma growth hormone and prolactin responses. The serum DAMME concentration was readily detectable when plasma growth hormone and prolactin had returned to control levels, but corticotrophin and cortisol were still significantly depressed.