Potentiation of canine pancreatic bicarbonate output by oleic acid is not neurally dependent.
To study neural involvement in potentiation of acid-induced pancreatic bicarbonate output, six dogs underwent extrapancreatic denervation and pancreatic fistula creation. Pancreatic responses to secretin (16 and 32 ng/kg/h) and cholecystokinin (50 ng/kg/h) were then assessed. The duodenum was then perfused with three sets of perfusates. The first set contained hydrochloric acid with either D- or L-phenylalanine. The second set contained bovine serum albumin and hydrochloric acid with or without oleic acid; the albumin and acid were varied so that each 50 ml contained 1, 2, or 4 meq titratable acid (pH 2.0-4.5). The third set was identical to the second except for initial pH of 3.5. Pancreatic responses predicted upon addition of cholecystokinin to secretin, L-phenylalanine to hydrochloric acid, or oleic acid to bovine serum albumin were compared with observed responses. At both doses, secretin-induced bicarbonate output was increased by cholecystokinin (16 ng/kg/h: 0.88 +/- 0.29 meq/15 min; 32 ng/kg/h: 1.01 +/- 0.23 meq/15 min). The latter significantly exceeded predicted output (16 ng/kg/h: 0.38 +/- 0.10 meq/15 min; 32 ng/kg/h: 0.58 +/- 0.15 meq/15 min), verifying potentiation. L-phenylalanine failed to potentiate bicarbonate output evoked by acidified D-phenylalanine. In contrast, addition of oleic acid to pH 2.0 or 3.5 bovine serum albumin potentiated bicarbonate output. These data suggest that enteropancreatic reflexes mediate potentiation of acid-induced pancreatic bicarbonate output by amino acids, but not by fatty acids.
Fink
A S
AS
Department of Surgery, University of Cincinnati Medical Center, Ohio.
Brodish
R J
RJ
Kuvshinoff
B W
BW
Irving
M
M
DeMar
A R
AR
D000818:Animals; D001639:Bicarbonates / Q000378:metabolism*; D003714:Denervation; D004285:Dogs; D009434:Neural Pathways / Q000187:drug effects; D019301:Oleic Acid; D009829:Oleic Acids / Q000494:pharmacology*; D010179:Pancreas / Q000187:drug effects* / Q000294:innervation* / Q000378:metabolism; D010185:Pancreatic Fistula; D010477:Perfusion; D010649:Phenylalanine / Q000494:pharmacology; D012710:Serum Albumin, Bovine
D001639:Bicarbonates; D009829:Oleic Acids; D012710:Serum Albumin, Bovine; D019301:Oleic Acid; D010649:Phenylalanine