Mortality, Growth and Liver Glycogen in Young Mice Exposed to Cold

Abstract

Mice of four strains were reared at 21°C. and then transferred to ‐3°C., in individual cages with nesting material. Controls were kept in similar conditions at 21°C. Many of the mice of two A strains died when stressed by cold at the age of 3 weeks, but none at 5 or 12 weeks. Many C57BL and GFF mice died when stressed at 5 weeks. Death usually occurred during the first 3 days, often on the first day. All stressed mice lost weight, especially in the first 2 days; if they survived, they made up the lost weight but they grew more slowly than the controls at all stages. Mice reared at ‐3°C. and stressed in that temperature when 3 weeks old had a lower mortality than those transferred from 21°C., and survivors did not lose weight. Mice reared at ‐3°C. and transferred to 21°C. at 3 weeks, although initially lighter, grew quickly and after 1 week were as heavy as the controls. Three‐week‐old mice stressed at ‐3°C. lost liver glycogen quickly whether they had been reared at 21°C. or ‐3°C. This was not due to a failure to eat, and there was no evidence that death resulted from inability to mobilize carbohydrate reserves.

Insufficient glucose supply is linked to hypothermia upon cold exposure in high-fat diet-fed mice lacking PEMT

“…Acute cold exposure also stimulates shivering thermogenesis in skeletal muscle to defend body temperature ( 12 ). Maintenance of body temperature upon acute exposure to cold depletes glycogen in the liver and is a high energy-consuming process ( 27,28 ). Thus, cold exposure challenges the cardiovascular system because of the high demand of energy supply for thermogenesis in BAT and skeletal muscle.…”

Studies on the Potentiation of Exdotoxin in Mice by Exposure to Cold

“…If this should also occur in cold exposed endotoxin poisoned mice, some of the energy normally available from catabolized protein might be lost because of elevated amino acid excretion. These pathways coupled with the greater energy requirements in animals maintained at low temperatures and the increased rate of carbohydrate catabolism (Barnett et al, 1960;Depocas and Masironi, 1960) would make carbohydrate shortage more critical than at room temperature. It is also reasonable to postulate an impairment in glyconeogenesis, particularly if reduced pyridine nucleotides or high energy phosphate are deficient, as recent unpublished findings suggest (Berry, unpublished).…”

Effects of a Cold Environment and Growth Rate on Reproductive Efficiency in Gilts

“…(Barnett and Manly 1960). Cold exposure in the rat (2 C) and mouse (-3 C) resulted in a prolonged estrous cycle and also delayed puberty in the mouse.…”