Depressor and regionally-selective vasodilator effects of human and rat urotensin II in conscious rats.
The regional haemodynamic effects of rat or human urotensin II (U-II) 3, 30, 300 and 3000 pmol kg(-1), i.v.) were assessed in separate groups of conscious, unrestrained, male, Sprague-Dawley rats (n=8 in each). Rat and human U-II had similar effects. At a dose of 3 pmol kg(-1), neither peptide had any significant action, while at a dose of 30 pmol kg(-1), there was a transient mesenteric vasodilatation (significant only for rat U-II). At doses of 300 and 3000 pmol kg(-1), there were dose-dependent tachycardias, and mesenteric and hindquarters hyperaemic vasodilatations. Thus, in conscious rats, the predominant cardiovascular action of rat and human U-II is vasodilatation. This is in contrast to recent findings with human U-II in non-human primates, but is consistent with effects on human isolated resistance vessels.
Gardiner
S M
SM
School of Biomedical Sciences, University of Nottingham Medical School, Queen's Medical Centre, Nottingham NG7 2UH.
March
J E
JE
Kemp
P A
PA
Davenport
A P
AP
Bennett
T
T
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D003864:Depression, Chemical; D004305:Dose-Response Relationship, Drug; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D008297:Male; D009842:Oligopeptides / Q000737:chemistry / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013152:Splanchnic Circulation / Q000187:drug effects; D014579:Urotensins / Q000494:pharmacology*; D014665:Vasodilator Agents / Q000494:pharmacology*
D009842:Oligopeptides; D014579:Urotensins; D014665:Vasodilator Agents; C029677:urotensin II