Influence of Cold on Liver Lipids of Rats at Different Levels of Dietary Protein

The effects of feeding diets containing various levels of casein, and of exposure to an environment of 6°,on food intake, growth and liver lipid composition of rats were studied. Rats exposed to cold ate more of all diets than rats maintained at normal ambient temperature. The growth rate at 6°was greater than at 23.5°when they were fed diets containing 5% protein or less, but on diets of 10% protein or more, growth rate was less. Liver triglycA©ride levels rose with decreased dietary protein intake in rats maintained at normal ambient temperature. However, exposing animals to 6°had a lipotropic effect. In contrast to the response of liver triglycA©rides, the rise of phospholipid levels, at low protein intake, was not prevented by exposing the animals to 6°. J. Nutr. 102: 401-408, 1972.