Comparision of Starvation Resistance and Lipid Metabosism between Two Lines of Mice Selected for Body Fat Percentage

Abstract

The selection of mice for high (SH) and low (SL) resistance to stavation had brought about the difference of fat accumulation between SH and SL lines. To clarify the relationship between body fat accumulation and survival time under starvation, two lines of mice for high (FH) and low (FL) body fat percentage were established through selection. Then, survival time and lipid metabolism between FH and FL were compared in the same method as in the SH and SL lines. At 63 days of age, there was significant difference (P<0.05) in survival time between FH (13.8 days) and FL (10.6 days), but this difference was not so large as the difference between SH (16 days) and SL (8 days). There was no difference in the fat cell number of epididymal adipose tissue between FH and FL, but the fat cell size of FH was larger than that of FL and these tendencies were the same as those between SH and SL lines. There was no significant difference between FH and FL lines in the lipase activity of adipose tissue and the incorporation of Na-¹⁴C-acetic acid into liver lipid, which were both significantly different between SH and SL lines. These results suggest that not only the fat accumulation but also other factors control the ability of survival under starvation.