Effect of Prolonged Cold Exposure on Hepatic Lipogenesis

¹ From the Department of Physiology, Tufts University School of Medicine, Boston, Massachusetts

Liver slices were prepared from ‘control’ rats kept at 25°C and from rats exposed to 0–2°C for 4–5 months. The ability of the tissue to convert acetate-1-C¹⁴ to C¹⁴O₂ and fatty acid-C¹⁴ was determined. Slices from the cold-exposed rats incorporated much less acetate-1-C¹⁴ into fatty acids than did the livers from ‘control’ rats. This depression in lipogenesis existed even though the carbohydrate content of the livers of cold-exposed rats was identical to that of livers from ‘control’ rats. Carbohydrate metabolism of the liver slices was also studied and no differences were found between those from ‘control’ and cold-exposed rats. It is apparent that the depressed hepatic lipogenesis of rats exposed to cold for prolonged periods of time is not associated with a reduced ability of the liver slices to metabolize carbohydrate.