长期高脂、高糖、高盐饮食对大鼠热和机械痛阈的影响

目的:观察长期高脂、高糖、高盐饲料饲养对正常大鼠热痛阈和机械痛阈的影响。方法:5周龄雄性SD大鼠30只,体重(100±5)g,随机分为高脂、高糖、高盐饲养组为A组(n=20)和正常饲养组为B组(n=10)。两组大鼠每日摄食、饮水不限。第1,10,20,30,40,50,60,70,120天时测量两组大鼠空腹血糖(fasting blood glucose,FBG)、空腹胰岛素(the fasting insulin,FINS)、热刺激缩足反应潜伏期(paw withdrawal thermallatency,PWTL)、机械刺激缩足反应阈值(pawwithdrawal mechanical threshold,PWMT)、体重、血压。结果:(1)A、B组大鼠空腹血糖均没有发生变化。(2)A组大鼠空腹血清胰岛素在20、30、40、50、60、70、120d明显升高,比较有明显差异(P<0.05),B组大鼠没有明显变化;(3)A组大鼠PWTL在70d以后出现明显下降(P<0.05),B组大鼠PWTL没有明显变化;(4)A组大鼠PWMT在60d出现明显下降(P<0.05),B组大鼠PWMT没有明显变化;(5)A组大鼠血压在20、30、40、50、60、70、120d明显高于B组,比较有明显差异(P<0.05);(6)A组大鼠体重与B组大鼠体重同时升高,在70d以后出现明显差异(P<0.05)。结论:高脂、高糖、高盐饲料饲养大鼠可以导致大鼠高血压,高胰岛素血症和胰岛素抵抗现象(饲养20d后)。在高脂、高糖、高盐饲料喂养下大鼠出现热痛敏(70d)和机械痛敏(60d),但与高血压、高胰岛素以及胰岛素抵抗现象不同时程出现。

The long-term effect of high fat-glucose-salt diet on pain threshold

AIM: To study the effect of the change of paw withdrawal thermal latency(PWTL) and paw withdrawal mechanical threshold(PWMT) in high fat-glucose-salt diet-fed rats.METHODS: Thirty five-week-old male Sprague-Dawley rats weighing(100±5)g were divided into two groups: Group A(n=20)(high fat-glucose-salt diet-fed) and Group B,the control group(n=10).Food and water available to both groups were not limited.FBG(fasting blood glucose),FINS(the fasting insulin),PWTL,PWMT,blood pressure and the weight were measured at the 1st,10th,20th,30th,40th,50th,60th,70th,120th day.RESULTS:(1)No change of FBG were found in the two groups.(2) Group A were significantly high in FINS after 20 days feeding,while that of the group B didn’t change.The difference became increasingly remarkable on the 20th,30th,40th,50th,60th,70th,and 120th day.(3)after 70 days feeding,PWTL of group A(P<0.05) obviously decreased,whereas that of group B didn’t.(4)PWMT of group A decreased after 60 days feeding(P<0.05),while that of group B didn’t.(5)The blood pressure of group A was noticeably higher than that of group B when measured on the 20th,30th,40th,50th,60th,70th,120th day.(6)The weight of both groups increased until the 70th day when significant differences were observed(P<0.05).CONCLUSION: High fat-glucose-salt diet can induce high blood pressure,hyperinsulinemic,insulin resistance(on the 20th day),thermal hyperalgesia(on the 70th day) and mechanical hyperalgesia(on the 60th day).But high blood pressure,hyperinsulinemic,insulin resistance didn’t appear at the same time with hyperalgesia.