AJP - Regulatory, Integrative and Comparative Physiology, Vol 263, Issue 3 517-R523, Copyright © 1992 by American Physiological Society

ARTICLES

Maintenance of intestinal nutrient transport during hibernation

H. V. Carey and N. S. Sills
Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison 53706.

We studied nutrient absorption across the brush-border membrane in jejunal tissues from active 13-lined ground squirrels and in hibernating squirrels that had not eaten for at least 6 wk. Body weights and jejunal wet weights per centimeter were significantly reduced in the hibernators. Rates of total and carrier-mediated uptake of 3-O-methylglucose (3-OMG) per centimeter intestinal length were greater in the active squirrels, but 3-OMG uptakes per milligram intestinal weight were greater in the hibernators, due to a significantly greater maximum rate of uptake (Jmax) per milligram with no differences in apparent Michaelis constant (Km). Passive permeabilities to L-glucose were similar in both groups. Total uptake of L-proline per centimeter was greater in active squirrels, but total proline uptake per milligram was greater in the hibernators due to a significantly greater Jmax per milligram with no difference in apparent Km. Na(+)-independent proline uptake accounted for a greater proportion of total proline uptake in active compared with hibernating squirrels. As a consequence, Na(+)-dependent proline uptake was greater in the hibernators when uptake was normalized either to intestinal length or intestinal weight. Thus hibernation is associated with an increase in the Jmax per milligram for 3-OMG and proline transport, as well as a shift in the Na+ dependency of proline uptake. We conclude that nutrient absorption is selectively retained in mammalian hibernators to maintain transport function after the extended winter fast.

This article has been cited by other articles:

				C. C. Kurtz, S. L. Lindell, M. J. Mangino, and H. V. Carey Hibernation confers resistance to intestinal ischemia-reperfusion injury Am J Physiol Gastrointest Liver Physiol, November 1, 2006; 291(5): G895 - G901. [Abstract] [Full Text] [PDF]

				H. V. CAREY, M. T. ANDREWS, and S. L. MARTIN Mammalian Hibernation: Cellular and Molecular Responses to Depressed Metabolism and Low Temperature Physiol Rev, October 1, 2003; 83(4): 1153 - 1181. [Abstract] [Full Text] [PDF]

				A. N. Alexander and H. V. Carey Oral IGF-I enhances nutrient and electrolyte absorption in neonatal piglet intestine Am J Physiol Gastrointest Liver Physiol, September 1, 1999; 277(3): G619 - G625. [Abstract] [Full Text] [PDF]