Effects of Na Pentobarbital Anesthesia on Serum Secretin and Exocrine Pancreatic Secretions

Abstract

The effect of Na pentobarbital anesthesia on serum secretin concentration and exocrine pancreatic secretion was investigated in dogs with chronic gastric and pancreatic fistulas. Na pentobarbital anesthesia was found 1) to reduce basal pancreatic flow rate by 74%, bicarbonate by 70% and protein secretions by 81% without affecting basal immunoreactive secretin (IRS) concentration; 2) to have no effect on HCl (9.6 mEq/30 min, intraduodenally) mediated IRS release but to reduce by approximately 50% HCl mediated bicarbonate output; 3) to have no effect on pancreatic responsiveness to stimulation by exogenous secretin (0.5 IU/kg x 30 min); 4) not to affect serum concentrations of IRS following secretin infusion. These data suggest 1) that basal pancreatic secretory functions are under control of tonic neural influences; 2) that Na pentobarbital anesthesia has no effect on IRS release but inhibits stimulated pancreatic bicarbonate secretion through suppression of an as yet unidentified agent; and 3) that Na pentobarbital does not affect the metabolism of secretin.

Furthermore, it was found that intraduodenal administration of 9.6 mEq of HCl and intravenous infusion of 0.5 IU/kg of secretin for 30 min both resulted in similar IRS concentrations of approximately 600 µU/ml (equivalent to 150 pg/ml).

Key words

Alert Dogs - Chronic Pancreatic Fistulas - Intraduodenal HCl - Intravenous Secretin