低氧训练过程中大鼠体重及能量代谢的变化

目的：研究低氧训练过程中大鼠体重、体成分、能量摄入及静息代谢率的变化，初步探讨低氧训练过程中大鼠体重变化与能量代谢变化间关系。方法：经过适应性训练筛选出的50只SD大鼠平均分为5组，保证每组大鼠体重基本一致，随机分为常氧安静组、常氧限食组、常氧训练组、低氧安静组、低氧训练组。训练组大鼠采用水平动物跑台进行耐力训练6周。试验期间每周称量大鼠体重，每3天称量一次大鼠食物摄入量。试验前、试验1周、3周、5周末测定大鼠静息代谢率，试验后处死大鼠并剥离其肾周、腹股沟脂肪及腓肠肌，称量其重量。结果：低氧训练组大鼠体重增幅除在第6周末与常氧训练组无显著性差异外，均显著性低于其他试验组，试验前3周其体重出现负增长。试验后低氧训练组大鼠肾周及腹股沟脂肪总含量显著低于其他试验组，而腓肠肌重量与其他组无显著性差异。低氧训练组大鼠试验期间总食物摄入量较其他各组大鼠低，尤其在前3周。低氧训练组大鼠静息代谢率先上升而后逐渐下降，至试验3周末时仍高于试验前值，试验5周末时降至低于试验前值（差异不显著），而除低氧安静组外的其他组大鼠静息代谢率则持续下降，至试验5周末时均显著性低于试验前水平。结论：从减缓体重增加幅度及对体成分的影响角度看，低氧训练减体重的效果优于限制饮食、耐力训练及低氧暴露。低氧训练过程中食物摄入量减少及静息代谢率增加可能是大鼠体重增长减缓的原因。

Changes of Body Weight and Energy Metabolism of SD Rats during Hypoxic Training

The purpose of this study was to investigate the change of body weight,body composition,energy intake and rest metabolic rate(RMR)of SD rats during hypoxic training,and discuss the relationship between the change of energy metabolism and body weight.Fifty adaptively trained SD rats were randomly divided into normoxic sedentary group(NS),normoxic food restricted group(NFR),normoxic training group(NT),hypoxic sedentary group(HS)and hypoxic training group(HT).The rats of training group performed endurance training on the level treadmill for 6 weeks.During the experiment,body weight and food intake were precisely weighed per week and every three day respectively.RMR were measured just before and 1,3 and 5 weeks after the beginning of the experiment.The fat pad of kidney and groin,gastrocnemius were obtained and precisely weighed after the rats were killed.The result showed that the amplitude of weight gain of HT rats was significantly less than those of the other groups except for NT rats on the end of 6th week,and in the first 3 weeks,the body weight of HT rats decreased absolutely.The total contents of fat pad of kidney and groin of HT rats were significantly less than those of other groups.And the difference of weight of gastrocnemius among each group was nonsignificant.The food intake of HT rats during the experiment was lower than those of the other groups,especially in the first 3 weeks.The RMR of the HT rats increased at the beginning and then decreased.RMR of HT rats after 3rd week was still higher than that before the experiment,and after 5th week it was lower than that before the experiment(nonsignificantly).The RMR of the other groups except for HS rats decreased continually and the value of RMR after 5th week was significantly lower than that before the experiment.Conclusion:Viewed on the points of the decrease of weight gain amplitude and the effects on the body composition,the effects on weight reduction of hypoxic training is better than that of food restriction,endurance training and hypoxic exposure.The decrease of food intake and the increase of RMR during the hypoxic training probably lead to the decrease of the weight gain.