Effects of pituitary adenylate cyclase activating polypeptide (PACAP) and vasoactive intestinal polypeptide (VIP) on the cardiovascular system in sheep.
The cardiovascular effects of PACAP and VIP were studied in intact conscious sheep; PACAP (0.008, 0.04, 0.2, and 1.0 nmol/min) and VIP (0.07, 0.2, 0.6, and 1.8 nmol/min) were infused in conscious sheep for periods of 10 min. For each peptide there was a dose-dependent increase in heart rate. At the highest doses tested, pulse pressure and mean arterial pressure tended to increase and decrease, respectively. However, only the decrease in mean arterial pressure following the highest dose of VIP reached significance. At the highest doses tested, heart rate increased nearly threefold during the infusion while mean arterial pressure declined by 18.5%. In individual animals the decrease in blood pressure and increase in heart rate occurred simultaneously, so that we were unable to conclude whether the increase in heart rate was due to a baroreceptor reflex.
Sawangjaroen
K
K
Department of Physiology and Pharmacology, University of Queensland, Australia.
Dallemagne
C R
CR
Cross
R B
RB
Curlewis
J D
JD
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002320:Cardiovascular Physiological Phenomena; D002319:Cardiovascular System / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D009479:Neuropeptides / Q000008:administration & dosage / Q000494:pharmacology* / Q000502:physiology; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D012756:Sheep; D014660:Vasoactive Intestinal Peptide / Q000008:administration & dosage / Q000494:pharmacology* / Q000502:physiology
D009479:Neuropeptides; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D014660:Vasoactive Intestinal Peptide