A MECHANISTIC STUDY OF THE FAILURE IN LIPOGENESIS INDUCED BY COLD-STRESS
Abstract
Liver homogenates for lipogenic studies were prepared from fed rats living at 25 C (control rats), fed rats exposed at 0 to 2 C for 1 day (cold-fed rats), and faste rats exposed at 0 to 2 C (cold-fasted rats). Sufficient TPN and isocitrate concentrations were added to yield an optimal TPNH generation for the fatty acids synthesizing system; CoA and HCO3 ion were also present at optimal concentrations. Liver homogenates from cold-fed rats synthesized fatty acids about as well as did homogenates from control rats. This finding contrasts with the almost complete absence of lipogenesis in the liver slice prepared from col -fed rats. The conclusion is drawn that the failure of lipogenesis in the intact liver cell of the coldfed rats does not result from the lack of fatty acid synthesizing enzymes, but is the result of an unfavorable cofactor environment. Liver homogenates from cold-fasted rats converted far less acetate-1-C14 to fatty acids than homogenates from control and cold-fed rats. It is concluded that either the concentration of the fatty acid synthesizing enzymes is greatly reduced, or a necessary unknown cofactor is not present at adequate levels in the liver of the cold-fasted rat. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1961
- Accession Number
- AD0261236
Entities
People
- E.j. Masoro