The effect of single injections of a dopaminergic agonist, apomorphine, on pituitary-adrenocortical function was investigated in healthy adult men by the measurement of plasma ACTH, beta-endorphin, cortisol and GH immunoreactivities. Single, subcutaneous injection of a subemetic dose of apomorphine (0.75 mg) resulted in a pronounced increase in plasma concentrations of GH, as well as ACTH, beta-endorphin, and cortisol, without induction of any serious adverse drug effects. These findings were confirmed in two separate experiments.