THE EFFECT OF PORTAL INFUSIONS OF EPINEPHRINE ON INGESTION, PLASMA-GLUCOSE AND INSULIN IN DOGS

Preabsorptive satiety has been hypothesized to occur as the result of food activating oral and gastrointestinal receptors that cause the release of catecholamines in the liver. The catecholamines were then proposed to hyperpolarize hepatic glucoreceptors and produce satiety. In the present study the hepatic portal vein was chronically cannulated in six mongrel dogs. Upon recovery the dogs were infused, over three minutes, with either saline or epinephrine (0.83 and 1.5 μg/kg b.wt.). Infusions ended 10 minutes prior to the animals' daily one-hour feeding period. The epinephrine infusions resulted in physiological increases in plasma glucose and insulin, but did not inhibit food consumption. The animals were next prefed 20% of their normal daily food intake 30 minutes prior to infusion of epinephrine at the above noted doses. Again plasma glucose and insulin increased, but food consumption was not affected. These data show that epinephrine infusions which produce physiological changes in plasma glucose and insulin do not alter feeding behavior of mongrel dogs. These findings are in agreement with previous data that question the physiological importance of the preabsorptive catecholamine satiety hypothesis. © 1990.