Spontaneous nocturnal plasma prolactin and growth hormone secretion in patients with Parkinson's disease and Huntington's chorea.

Plasma prolactin (PRL) and growth hormone (GH) levels were measured in 8 patients with Parkinson's disease (PD) and in 6 patients with Huntington's chorea (HC) during the night. The sleep was evaluated with all-night poligraphic recordings. Plasma PRL levels were significantly lower in parkinsonian patients than in age-matched controls. Plasma GH values did not differ between the two groups. In HC patients no statistically significant differences were found in the PRL and GH secretory patterns when compared to the age-matched control subjects. These data indicate that changes of nocturnal PRL and GH profile in PD and HC patients in respect to age-matched healthy subjects, may be present, but a straight forward differentiation among groups is not possible because of the wide individual variations.