Effects of Living High-Training Low on Fat Metabolism of Rats

• 1、College of Soprts Science,Beijing Sport University,Beijing 100084
• 2、Beijing Competitor Sports Science and Technology co., LTD, Beijing 100084

Abstract：Objective: The purpose of this study was to investigate the effect of living high-training low (HiLo) on the synthesis and decomposition of fat in rats. Method: Thirty two 8-wk-old male SD rats were randomly assigned to 4 groups: normoxia stability group(control group)(NS)，normoxia training group (NT), hypoxia stability group (HS), hypoxia training group (HT).With hypoxia group into the hypoxia chamber 12 hours/day, the air pressure was 12.5% (which imitates the environment of 4000M above the sea level), and with the rest of time living in the normal air pressure. Both NT and HT groups took part in running in the treadmill under normoxia environment for 3 weeks (treadmill grade 10%, speed 25m/min, one bout per day, 5 bouts per week and 60 min per bout). After 3 weeks' training, each group was given nothing to eat for 12 hours. After chloral hydrate anesthesia, we measured each group with their weight and body composition as well as blood abdominal aorta and their leptin level in the serum. White adipose tissue (WAT) and brown adipose tissue (BAT) were taken after executing the rats. Ater that, RT-PCR was applied to investigate how HSL, ACC1 and PPAR-γ's genetic expression change. Results: (1) In the condition of normoxia and hypoxia, NT and HT added less weight than NS and HS (P<0.05). At the same time, HT added less weight than NT (P<0.05). (2) The WAT of HT was less than HS (P<0.05), also, the BAT of HS was less than NT (P<0.05). (3) The increasing of fat and muscle in HT was less than NS (P<0.05). The weight of muscle in HT was less than NT (P<0.05). (4) The intensity of leptin in NT was higher than NS, while the level of HS and HT was higher than NS. 5) HSL, ACC1 mRNA in the BAT of NT expressed less than NS (P<0.05); HSL mRNA in the white fat of HS expressd higher than NS (P<0.05). 6) Compared with NS, the level of BAT and WAT in other groups' PPAR-γ mRNA rised without significance, which indicate that there was no regular change. Conclusion: Intermittent hypoxia and exercise can negatively influence the gain of weight, muscle and fat. It also can stipulate the secretion of Leptin, which may be related to decrease the growth of weight and fat. Intermittent hypoxia and exercise can reduce the speed of BAT's composition and decomposition, decrease the metabolic rate, raise the speed of WAT's composition and decomposition, and increase the metabolic rate. The PPAR-γ which regulates the lipid metabolic had no regular change.

Keywords： HiLo（living high-training low） Lipid metabolism Leptin Body composition