QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Kaul, L. Articles by Berdanier, C. D. Search for Related Content PubMed PubMed Citation Articles by Kaul, L. Articles by Berdanier, C. D.

Effect of Meal-feeding on the Daily Variations of Insulin, Glucose, and NADP-linked Dehydrogenases in Rats^1,2,

Department of Foods, Nutrition and Institution Administration, College of Human Ecology, University of Maryland, College Park, Maryland 20740, and Carbohydrate Nutrition Laboratory, Nutrition Institute, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, Maryland 20705

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 and altered with respect to the peaks and nadirs when feeding was restricted to one 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.

KEY WORDS: • meal-feeding • circadian rhythms • insulin • glucose

¹ A preliminary report of these data was presented at the 56th Annual Meeting of the Federation of American Societies for Experimental Biology, April 1972.

² Data are from a dissertation submitted by Lalita Kaul to the Graduate School, University of Maryland, in partial fulfillment of the requirements for the Ph.D. degree.

³ Present address: Department of Foods and Nutrition, Howard University, Washington, D.C.

⁴ Present address: Department of Biochemistry, University of Nebraska College of Medicine, Omaha, Nebr.

Manuscript received 26 December 1974.