Effect of meal-feeding on the daily variations of insulin, glucose, and NADP-linked dehydrogenases in rats.
Normal and adrenalectomized rats were either ad libitum fed or meal-fed a 66.5% glucose diet for 1 to 3 weeks. Ad libitum-fed rats exhibited synchronized daily rhythms in the levels of immunoreactive insulin, glucose, hepatic glucose-6-phosphate dehydrogenase, and malic enzyme activities. These rhythms were shifted late-morning 2-hour feeding period. The rhythms of adrenalectomized ad libitum-fed rats were different from those for nonadrenalectomized rats. These results indicate that differences between ad libitum- and meal-fed animals may be attributable to the timing of food intake with respect to the timing of observation rather than to meal-feeding alone. It is further concluded that the adrenals play a role in the maintenance of these rhythms.
D000311:Adrenal Glands / Q000502:physiology; D000315:Adrenalectomy; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism*; D002940:Circadian Rhythm; D005247:Feeding Behavior; D005954:Glucosephosphate Dehydrogenase / Q000378:metabolism*; D007328:Insulin / Q000097:blood*; D008099:Liver / Q000201:enzymology*; D008291:Malate Dehydrogenase / Q000378:metabolism*; D008297:Male; D051381:Rats
D001786:Blood Glucose; D007328:Insulin; D008291:Malate Dehydrogenase; D005954:Glucosephosphate Dehydrogenase