| Abstract: | Immunoreactive plasma human prolactin (HPr) and human growth hormone (HGH) concentrations were measured in six normal young men with polygraphic sleep monitoring during normal sleep and during sleep in which l-dihydroxyphenylalanine (l-DOPA) was infused intravenously at a rate of 0.8 to 1.0 mg/min. The intravenous infusion of l-DOPA significantly suppressed the episodic release of HPr during sleep and the occurrence of rapid eye movement (REM) sleep. However, HGH release during sleep was not remarkably influenced by l-DOPA. These results suggest that central catecholaminergic neural mechanisms are related to both sleep-related HPr release and REM sleep, but do not play an important role in sleep-related HGH release. |
