Effect of clonidine on growth hormone, prolactin, luteinizing hormone, follicle-stimulating hormone, and thyroid-stimulating hormone in the serum of normal men
Lal, S.; Tolis, G.; Martin, S.B.; Brown, G.M.; Guyda, H.
Journal of Clinical Endocrinology and Metabolism 41(5): 827-832
ISSN/ISBN: 0021-972X PMID: 1184719 DOI: 10.1210/jcem-41-5-827
Clonidine (0.15 mg iv), a selective noradrenergic receptor agonist, increased serum growth hormone (GH) levels (greater than 6 ng/ml) on 8 out of 12 administrations to 6 normal men. This increase was independent of the hypotensive effects of the drug and unrelated to changes in serum cortisol. Clonidine induced a hyperglycemic effect in all subjects which was greatest 15 min after commencint the injection. No changes in blood sugar or GH occurred after placebo injection. Apomorphine, a selective dopamine receptor agonist, elevated GH in each of these 6 subjects (greater than 10 ng/ml). Clonidine had no effect on serum prolactin (PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), or thyroid-stimulating hormone (TSH). These data are compatible with a dual dopaminergic and noradrenergic mechanism modulating GH secretion in normal men and with the absence of a noradrenergic mechanism in the regulation of PRL, LH, FSH, or TSH.