Ishibashi M, Yamaji T, Takaku F, Teramoto A, Fukushima T, Toyama M, Kamoi K
Third Department of Internal Medicine, Faculty of Medicine, University of Tokyo, Japan.
Acta Endocrinol (Copenh). 1987 Sep;116(1):81-4. doi: 10.1530/acta.0.1160081.
The effect of GnRH-associated peptide on PRL secretion by human pituitary lactotropes in culture was studied. Pituitary adenomas obtained at selective transsphenoidal adenomectomy from a patient with prolactinoma, and two patients with mixed GH- and PRL-secreting pituitary adenomas were cultured in monolayer. When cells were incubated with dopamine (10 nmol/l), a significant inhibition in PRL secretion was observed in all the experiments, which was blocked by co-incubation with haloperidol. In mixed GH- and PRL-secreting adenoma cells, dopamine likewise decreased GH secretion. Incubation of cells with synthetic GnRH-associated peptide at concentrations up to 100 nmol/l, on the other hand, failed to affect both PRL and GH secretion. These results suggest that synthetic GnRH-associated peptide has no inhibitory effect on PRL secretion in human pituitary lactotropes.
