Effect of endothelin-1 in man—Impact on basal and stimulated concentrations of luteinizing hormone, follicle-stimulating hormone, thyrotropin, growth hormone, corticotropin, and prolactin

Abstract

The effect of endothelin-1 on basal and stimulated serum (plasma) concentrations of luteinizing hormone (LH), follicle-stimulating hormone (FSH), thyrotropin (TSH), prolactin (PRL), growth hormone (GH), and corticotropin was investigated in healthy male volunteers (n = 5). Intravenous (IV) administration of endothelin-1 (5 ng/kg/min for 15 minutes, followed by 2.5 ng/kg/min for 105 minutes) induced an increase in basal plasma concentrations of corticotropin. Serum concentrations of PRL, TSH, LH, FSH, and GH remained unchanged. The increase in serum concentrations of these pituitary hormones induced by IV administration of LH-releasing hormone ([LH-RH] 100 μg), thyrotropin RH ([TRH] 400 μg), GH-RH (100 μg), and corticotropin-releasing factor ([CRF] 100 μg) was suppressed in regard to PRL ( P < .01) and GH ( P < .01) and enhanced in regard to corticotropin ( P < .01). Stimulated serum concentrations of LH and FSH also tended to be higher following administration of endothelin-1 ( P < .05), whereas the increase in serum concentrations of TSH remained unchanged. Thus, when administered in pharmacological doses, endothelin-1 influences pituitary hormone secretion in man.