Influence of environmental conditions on exocrine pancreatic response to intravenous injection of ethanol or 2-deoxyglucose in the dog

When dogs have free access to the outside, an intravenous injection of ethanol depresses secretin-stimulated exocrine pancreatic secretion by a vagally mediated mechanism. This was shown in two separate series of six and seven dogs each. When dogs were kept in air-conditioned windowless kennels, the response to a meal was unchanged but the response to ethanol was reversed to stimulation. In four dogs, ethanol 1 g/kg was given during a secretin infusion. Three months after changing from open to closed kennels the inhibition (–86% for protein output) was still present, but after 6 months ethanol produced a stimulation (+62%) of pancreatic secretion. This increase was abolished, but not reversed, by keeping the animals outside during the day for four weeks, whereas after three months there was a partial restoration of the inhibitory effect (–39%). In contrast, changing from an open to a closed kennel changed the initial response to 2-deoxy-d-glucose (2-DG), 100 mg/kg, from stimulation to inhibition. These results suggest that environmental conditions affect the cranial regulation of pancreatic secretion.