泽泻汤加味方对高盐高血压大鼠肾脏AQP-2表达的影响

Effect of Modified Zexie Decoction on Renal Aquaporin-2 Expression in Hypertension Rats Induced by High-Salt

目的探讨泽泻汤加味方对高盐高血压大鼠肾脏水通道蛋白(AQP)-2表达的影响。方法以8%高盐饲料喂养的方法制备高盐高血压动物模型50只,造模成功后随机分为模型组,西药组,中药高、中、低组,各10只;另选10只普通饲料喂养大鼠为正常组。中药高、中、低组分别给予泽泻汤加味方混悬液16.2、10.8、5.4 g/(kg·d);西药组给予缬沙坦氢氯噻嗪溶液16.65 mg/(kg·d);模型组及正常组灌服等体积蒸馏水。均按每天1 m L/100 g灌胃,灌胃4周。于给药1、4、7、14、28 d时测定大鼠收缩压(SBP),并收集24 h尿量。用免疫组织化学法和逆转录-聚合酶链反应(RT-PCR)分别检测肾脏AQP-2蛋白和m RNA的表达。结果 SBP由高到低依次是:模型组>中药中组和中药低组>西药组和中药高组>正常组,尿量由高到低依次是:西药组和中药高组>中药中组和中药低组>模型组>正常组,中药中组与中药低组间、西药组与中药高组间差异无统计学意义。模型组肾脏AQP-2沿集合管内壁上皮细胞分布的棕黄色颗粒较正常组及中药高、中、低组明显颜色加深而浓厚,分布面积更广泛。除中药低组AQP-2m RNA的表达水平与模型组差异无统计学意义外,其余各组均低于模型组,高于中药高组(均P<0.05)。结论泽泻汤加味方可通过抑制AQP-2的高表达使血压降低。

Objective To explore the effect of modified Zexie Decoction on renal aquaporin-2（AQP2） expressionin high-salt hypertensive rat. Methods Hypertensive rats model was established by feeding rat with 8% high salt. Rats（n=50） were divided into model group, modern medicine group, traditional Chinese medicine groups of high, medium, low dose,with 10 rats in each group. The other 10 rats were fed with ordinary diet as normal group. Rats in traditional Chinese medi-cine of high, medium, low groups were given Zexie Decoction suspension of 16.2, 10.8 and 5.4 g/（kg·d） respectively; Rats inmodern medicine group was given Valsartan hydrochlorothiazide 16.65 mg/（kg·d）; the model group and normal group was ad-ministered with equal volume of distilled water. Animals were feed with medications at 1 m L/100 g by gavage for 4 weeks.On the 1st, 4th, 7th, 14 thand, 28 thday of administration, we measured SBP and collected 24 h urine. We employed immunohis-tochemistry to detect renal AQP-2 protein expression level and RT- PCR to detect renal AQP-2 m RNA transcription level.Results The rank of SBP from high to low is： model group traditional Chinese medicine medium and low dose groups traditional Chinese medicine high dose group and western medicine group normal group. The rank of urine volume fromhigh to low is： Western medicine group and traditional Chinese medicine high dose group traditional Chinese medicine me-dium and low dose group normal group, the difference was not statistically significant between traditional Chinese medi-cine medium and low dose group, or between western medicine group and traditional Chinese medicine high dose group.The renal AQP- 2 in epithelial cells along the collecting duct wall of rats in model group show brown particles which aredarker and wider distributed than those in normal group and traditional Chinese medicine of high, medium, low dose groups.RT- PCR results show that AQP-2 m RNA expression is highest in rats of model group and lowest in rats of traditional Chi-nese medicine high dose group（P〈0.05）. No statistical significance of AQP m RNA level was found between traditional Chi-nese medicine low group and model group（P〈0.05）. Conclusion Modified Zexie Decoction can lower blood pres-sure by inhibiting the expression of AQP-2.