间歇性低氧和运动对高脂饮食诱导胰岛素抵抗大鼠血清内脂素的影响

目的:探讨间歇性低氧和运动对高脂饮食诱导的胰岛素抵抗大鼠血清内脂素的影响。方法:将72只雄性SD大鼠随机分为普通对照组(12只)和高脂造模组(60只),高脂造模组给予高脂饲料。6周末随机取12只高脂造模组大鼠处死,普通对照组同期处死,测试其空腹血糖和胰岛素水平,根据胰岛素抵抗指数(HOMA-IR)确定造模成功后,将其余48只高脂造模组大鼠分为常氧安静组、低氧安静组、常氧运动组和低氧运动组,每组各12只。低氧组暴露在14.5%氧浓度的环境中,4h/d,7d/w;运动组常氧状态下以20m/min进行跑台运动,1h/d,5d/w。4周末,测试各组大鼠血糖、血胰岛素、血清内脂素和内脏脂肪总量等指标。结果:6周高脂饮食后,高脂组大鼠胰岛素抵抗指数显著升高,造模成功。与常氧安静组比较,低氧安静组、常氧运动组胰岛素抵抗指数和血清内脂素均显著下降(P<0.01);低氧运动组血清内脂素较常氧运动组显著升高(P<0.01),与常氧安静组比较无显著性差异(P>0.05)。结论:间歇低氧和有氧运动均可有效改善胰岛素抵抗,并降低血清内脂素水平;而间歇低氧和运动双重作用对血清内脂素的影响不显著。

Influence of Intermittent Hypoxic Exposure and Exercise on the Plasma Level of Visfatin in Rats with Insulin Resistance Induced by High Fat Diet

Objective In this study,the effect of intermittent hypoxic exposure and exercise on the plasma visfatin concentrations was investigated in rats with insulin resistance(IR) induced by high fat diet.Methods Seventy male SD rats were randomly divided into high fat diet(HFD) group(60) and control group(12).Rats in control group were fed with regular diet and rats in HFD group were fed with self made HFD.After 6 weeks,the fasting blood glucose(FBG) and fasting insulin(FIN) levels from 12 of the HFD group were measured,then the insulin resistance index(HOMA-IR) was evaluated.The remaining rats in HFD group were randomly divided into four groups: sedentary normoxic(SN) group,sedentary hypoxic(SH) group,trained normoxic(TN) group and trained hypoxic(TH) group.The rats in hypoxic group stayed under the hypoxic condition(14.5% of oxygen) for 4 hours per day,7 days per week and the rats in trained group ran on treadmill at the speed of 20 m/min under normoxic condition,5 days per week.After four weeks,all rats were fasted for 12 hours,and then the plasma levels of visfatin and insulin were checked in each group.The fat of epididymis and the fat pad of kidney were used as visceral fat mass.Results IR was successfully induced by 6-week HFD.The plasma level of visfatin in TH group and SH group reduced obviously(P< 0.05) as compared with that in SN group;but improved obviously in TH group(P< 0.01) as compared with that in TN group.Conclusions Intermittent hypoxic exposure and exercise could lower the plasma visfatin concentrations in rats with IR.