| Abstract: | We studied the acute effects of pharmacologic stimulation of neurotransmitter systems implicated in growth hormone and prolactin regulation in eight patients with Huntington's disease and matched control subjects. Both apomorphine, a dopamine agonist, and muscimol, a GABA agonist, produced an exaggerated rise in plasma growth hormone levels in the Huntington patients. Neither the growth hormone response to a muscarinic agonist, arecoline, nor the prolactin response to any of these drugs differed in the patients and controls. Loss of somatostatin activity in the hypothalamic-pituitary axis in Huntington's disease could account for these endocrinologic changes. |
