Relation of fatty acids to feeding behaviour: effects of palmitic acid infusions, lighting variation and pent 4 enoate, insulin or propranolol injection

Intravenous infusion of palmitic acid in the day or in the night was found neither to inhibit nor to facilitate feeding in the rat. The results showed only a night-phase inhibition when infusion approached a calorically substantial rate and this effect was produced both by the palmitic acid-albumin complex and by the albumin vehicle alone. The well-known increase in rate of feeding at light offset was closely controlled by lighting, rather than by duration of the daytime fat mobilizing phase. Pent-4-enoic acid, an inhibitor of fat oxidation, did not increase food intake during the day. Insulin increased food intake not only by day when it would prevent fat mobilization, but also at night, when no mobilization normally occurs. Propranolol, a blocker of beta adrenergic fat mobilization, had only inhibitory effects on feeding. Under isolation conditions, propranolol injection shortened the latency of meal by day, but so did saline injection. It is concluded that, although fat no doubt ultimately enters into the caloric control of feeding, there is as yet no evidence that circulating fatty acids have large short-term effects on food intake. Relation of fatty acids to feeding behaviour: Effects of palmitic acid infusions, lighting variation and Pent4-enoate, insulin or propranolol injection1 - ResearchGate.