Pancreatic polypeptide response to ethanol in humans and dogs

We studied the effect of a drink of various concentrations of pure ethanol and several commonly ingested alcoholic beverages on plasma levels of immunoreactive pancreatic polypeptide in six healthy human volunteers and compared the results to a protein-rich meal. A drink of distilled water (250 ml) and of pure ethanol (250 ml or 125 ml in the case of 40% v/v ethanol) in concentrations (4, 10, 20, and 40%, v/v) normally present in beer, wine, liquor and whisky did not stimulate plasma pancreatic polypeptide levels above basal. Neither beer, red and white wine (250 ml each) nor whisky (125 ml) caused an increase in basal plasma pancreatic polypeptide levels. The 90-min integrated plasma pancreatic polypeptide response to the protein-rich meal was significantly reduced by an additional drink of 250 ml of white wine ($\text{5987 ± 1315}$ versus $\text{4126 ± 809}\text{pmol · min}{}^{\mathrm{?1}}\text{· 1}{}^{\mathrm{?1}}$). An intravenous infusion of ethanol (300 mg · kg^?1 over 30 min) did not increase plasma pancreatic polypeptide levels above basal.In six dogs with gastric and duodenal fistulas the infusion of pure ethanol into a peripheral vein, into the stomach or into the duodenum did not alter plasma pancreatic polypeptide levels. When ethanol (200 ml of either 1.8, 10 or 40%, v/v) was given as an intragastric bolus injection, only 40% ethanol caused an increase in the mean 90-min integrated plasma pancreatic polypeptide response which was only one-twelfth of the pancreatic polypeptide response to an oral mixed meat meal (35 g · kg^?1). We conclude that in man neither an intravenous infusion nor a drink of ethanol in concentrations normally present in beer, wine and whisky, release pancreatic polypeptide. Also, beer, red and white wine and whisky have no effect on plasma pancreatic polypeptide concentrations. In dogs, a large amount of intragastric ethanol was needed to produce a very small rise in plasma pancreatic polypeptide levels. These results do not favour the hypothesis that, in man and dog, pancreatic polypeptide is the hormonal mediator of the ethanol induced inhibition of exocrine pancreatic secretion.