Dose-response effect of intraduodenal HCl on exocrine pancreatic secretion, portal secretin, and VIP plasma levels in anesthetized rats.
In anaesthetized rats, a dose-dependent effect of different intraduodenal HCl loads (0.6, 1.2, 6 and 12 mmol/h) on exocrine pancreatic secretion and plasma levels of secretin and VIP has been observed. The flow rate of pancreatic juice showed a significant increase at all the doses used; the integrated percentage response (IPR) of flow were 359%, 595%, 894% and 1371% for, respectively, 0.6, 1.2, 6 and 12 mmol/h. The increase of protein output only achieved statistical significance at HCl loads of 6 mmol/h or more; the IPR of protein output were 153%, 305%, 320% and 420% for, respectively, 0.6, 1.2, 6 and 12 mmol/h HCl. Portal levels of secretin and VIP were measured by specific radioimmunoassays. Significant increase of secretin concentration was observed at HCl loads of 1.2 mmol/h or more, whilst VIP levels only increased significantly after intraduodenal HCl load of 6 mmol/h or more. The IPR of secretin release were 180%, 203%, 280% and 322% for, respectively, 0.6, 1.2, 6 and 12 mmol/h HCl and IPR of VIP release were 3%, 20%, 244% and 315% for, respectively, 0.6, 1.2, 6 and 12 mmol/h HCl. Our results suggest that secretin may play a more prominent role than VIP in stimulating exocrine pancreatic secretion in response to intraduodenal loads of acid in this species.
García
L J
LJ
Department of Physiology and Pharmacology, Faculty of Biology, University of Salamanca, Spain.
Minguela
A
A
Calvo
J J
JJ
López
M A
MA
D000777:Anesthetics; D000818:Animals; D004305:Dose-Response Relationship, Drug; D004386:Duodenum; D006851:Hydrochloric Acid / Q000008:administration & dosage*; D008297:Male; D010179:Pancreas / Q000187:drug effects* / Q000378:metabolism; D010477:Perfusion; D011169:Portal Vein; D051381:Rats; D017208:Rats, Wistar; D012633:Secretin / Q000097:blood*; D014660:Vasoactive Intestinal Peptide / Q000097:blood*
D000777:Anesthetics; D012633:Secretin; D014660:Vasoactive Intestinal Peptide; D006851:Hydrochloric Acid