Effect of pancreatectomy or adrenalectomy on the responses of rats to meal-feeding.
The effects of partial pancreatectomy or adrenalectomy and insulin or corticosterone replacement on the responses of rats to meal-feeding were studied. Partial pancreatectomy lowered glucose-6-phosphate dehydrogenase (G6PD) and malic enzyme (ME) activities and resulted in higher blood glucose levels. Partial pancreatectomy did not affect the ability of the animals to adapt to meal-feeding. Insulin supplementation of the pancreatectomized rats restored G6PD and ME activities to those observed in the intact animals and normalized the blood glucose levels in the ad libitum-fed rats. Adrenalectomy decresed the survival of rats subjected to meal-feeding. Eighty percent of the rats died when meal-fed a high glucose diet. Survival was improved when either a 66.5% starch diet or a 40.5% fat diet was substituted for the 66.5% glucose diet. Adrenalectomized meal-fed animals fed 66.5% glucose had higher G6PD and ME activities and higher liver lipid levels than both the adrenalectomized ad libitum-fed and the sham-operated meal-fed rats. Glucocorticoid supplementation lowered G6PD activity in the adrenalectomized meal-fed rats but had no effect on ME activity or liver lipid. Meal-fed adrenalectomized rats had lower liver and serum cholesterol levels than meal-fed intact rats and ad libitum-fed adrenalectomized rats. These cholesterol levels were increased with glucocorticoid supplementation. It was concluded that adaptation to meal-feeding involves an adrenal response to the periodic absence of dietary energy intake, and that the degree of involvement of this response is determined by the composition of the diet.
D000311:Adrenal Glands / Q000502:physiology*; D000315:Adrenalectomy; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D002784:Cholesterol / Q000097:blood; D004040:Dietary Carbohydrates / Q000008:administration & dosage; D004041:Dietary Fats / Q000008:administration & dosage; D005247:Feeding Behavior; D005938:Glucocorticoids / Q000494:pharmacology; D005947:Glucose / Q000494:pharmacology; D005954:Glucosephosphate Dehydrogenase / Q000378:metabolism; D007328:Insulin / Q000097:blood; D050356:Lipid Metabolism; D008099:Liver / Q000378:metabolism; D008291:Malate Dehydrogenase / Q000378:metabolism; D008297:Male; D010179:Pancreas / Q000502:physiology*; D010180:Pancreatectomy; D051381:Rats; D013213:Starch / Q000494:pharmacology
D001786:Blood Glucose; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D005938:Glucocorticoids; D007328:Insulin; D013213:Starch; D002784:Cholesterol; D008291:Malate Dehydrogenase; D005954:Glucosephosphate Dehydrogenase; D005947:Glucose