Comparison between the effects of VIP and the novel peptide PACAP on the exocrine pancreatic secretion of the rat.
The effect of intravenous infusion of pituitary adenylate cyclase-activating peptide (PACAP) 27, a novel regulatory peptide that shows a close structural and chemical similarity to vasoactive intestinal peptide (VIP), on the rat exocrine pancreatic secretion was studied. PACAP and VIP stimulated the flow rate of exocrine pancreatic secretion (p < 0.05). However, protein output and amylase secretion were mainly stimulated by PACAP. Intravenous infusion of VIP increased the plasma levels of secretin (p < 0.05). On the other hand, PACAP released neither secretin nor VIP. Our results show: (a) both PACAP and VIP stimulate exocrine pancreatic secretion, (b) PACAP stimulation of pancreatic amylase and protein secretion is greater than that induced by VIP, and (c) PACAP probably exerts a direct effect on exocrine pancreas whereas some of the actions of VIP might be mediated by secretin.
Alonso
R M
RM
Departamento de Fisiología y Farmacología, Universidad de Salamanca, Spain.
Rodríguez
A M
AM
García
L J
LJ
López
M A
MA
Calvo
J J
JJ
D000681:Amylases / Q000378:metabolism; D000818:Animals; D008297:Male; D009479:Neuropeptides / Q000494:pharmacology*; D018377:Neurotransmitter Agents / Q000494:pharmacology*; D010179:Pancreas / Q000187:drug effects / Q000378:metabolism*; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D051381:Rats; D017208:Rats, Wistar; D012633:Secretin / Q000378:metabolism; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism / Q000494:pharmacology*
C495403:Adcyap1 protein, rat; D009479:Neuropeptides; D018377:Neurotransmitter Agents; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D012633:Secretin; D014660:Vasoactive Intestinal Peptide; D000681:Amylases