Regional haemodynamic effects of human alpha- and beta-calcitonin gene-related peptide in conscious Wistar rats.
1. A comparative study was carried out to assess the regional haemodynamic effects of intravenous infusion of human alpha- and beta-calcitonin gene-related peptide (CGRP; 0.006, 0.06 and 0.6 nmol h-1) in conscious, unrestrained Wistar rats. 2. With human alpha-CGRP, tachycardia was always accompanied by a fall in mean arterial blood pressure (MBP), but human beta-CGRP at the middle dose caused tachycardia with no significant hypotension. 3. Human alpha- and beta-CGRP both caused dose-dependent falls in MBP accompanied by common carotid and hindquarters vasodilatations and increased flows. The highest dose of alpha- and beta-CGRP caused mesenteric vasoconstriction and renal vasodilatation, but the latter was not associated with an increase in flow. 4. With the intermediate dose, human alpha-CGRP caused more significant haemodynamic changes than did human beta-CGRP. In addition, comparison with previous experiments involving infusion of rat alpha-CGRP indicated that human alpha-CGRP had more potent haemodynamic effects than the former.
Gardiner
S M
SM
Department of Physiology and Pharmacology, Medical School, Queen's Medical Centre, Nottingham.
Compton
A M
AM
Bennett
T
T
D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000008:administration & dosage / Q000494:pharmacology*; D006439:Hemodynamics / Q000187:drug effects*; D006614:Hindlimb / Q000098:blood supply; D006801:Humans; D007262:Infusions, Intravenous; D007536:Isomerism; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012039:Regional Blood Flow / Q000187:drug effects; D012079:Renal Circulation / Q000187:drug effects; D013152:Splanchnic Circulation / Q000187:drug effects; D014655:Vascular Resistance
D015740:Calcitonin Gene-Related Peptide