Urotensin II Acts Centrally to Increase Epinephrine and ACTH Release and Cause Potent Inotropic and Chronotropic Actions

Publisher Website
Google Scholar
Abstract
Urotensin II is a small peptide whose receptor was recently identified in mammals as the orphan G protein–coupled receptor-14. The reported cardiovascular responses to systemic urotensin II administration are variable, and there is little detailed information on its central cardiovascular actions. We examined the cardiovascular and humoral actions of intracerebroventricular urotensin II (0.02 and 0.2 nmol/kg and vehicle) and intravenous urotensin II (2, 20, and 40 nmol/kg and vehicle) in conscious ewes previously surgically implanted with flow probes and intracerebroventricular guide tubes. Two hours after intracerebroventricular infusion of urotensin II (0.2 nmol/kg over 1 hour; n=5), heart rate (+56±13 beats per minute [bpm]), dF/dt (an index of cardiac contractility; +533±128 L · min−1 · s−1), and cardiac output (+3.4±0.4 L/min) increased significantly compared with vehicle, as did renal, mesenteric, and iliac blood flows and conductances. Plasma epinephrine, adrenocorticotropic hormone, and glucose le...

This publication has 33 references indexed in Scilit: