目的 探讨缬沙坦对颈动脉粥样硬化大鼠血管紧张素Ⅱ 1型受体（AT1R）/磷脂酰肌醇3激酶（PI3K）/蛋白激酶B（Akt）/哺乳动物雷帕霉素靶蛋白（mTOR）通路及血管内皮细胞自噬的影响。方法 采用高脂饲料饲喂结合颈动脉球囊损伤法制备颈动脉粥样硬化大鼠模型，随机分为模型组（生理盐水），缬沙坦低、中、高（10、20、30 mg/kg）剂量组和阳性对照组（阿托伐他汀，2.5 mg/kg），另取假手术大鼠作为对照组（生理盐水），每组15只，均每天ig给药1次，连续4周，给药体积10 mL/kg。末次给药结束24 h后，全自动生化分析仪检测各组大鼠血脂水平，包括总胆固醇（TC）、三酰甘油（TG）、低密度脂蛋白胆固醇（LDL-C）和高密度脂蛋白胆固醇（HDL-C）；酶联免疫吸附（ELISA）法检测各组大鼠颈动脉血清中白细胞介素6（IL-6）、白细胞介素1β（IL-1β）和肿瘤坏死因子α（TNF-α）水平；苏木精-伊红（HE）染色观察各组大鼠颈动脉内皮组织病理学变化；单丹磺酰尸胺（MDC）染色法检测各组大鼠颈动脉内皮细胞自噬率；蛋白免疫印迹（Western blotting）法检测各组大鼠自噬标记蛋白LC3-Ⅱ、Beclin 1和通路蛋白AT1R表达水平及PI3K、Akt、mTOR磷酸化水平。结果 与对照组相比，模型组大鼠颈动脉组织内皮细胞排列紊乱，内皮破损，大量炎性因子浸润，TC、TG、LDL-C、IL-1β、TNF-α、IL-6水平及AT1R蛋白表达和PI3K、Akt、mTOR磷酸化水平显著升高（P<0.05），HDL-C水平、细胞自噬率、LC3-Ⅱ和Beclin 1蛋白表达水平显著降低（P<0.05）；与模型组相比，缬沙坦低、中、高剂量组大鼠颈动脉组织中内膜逐渐平滑，炎性因子浸润依次减少，TC、TG、LDL-C、IL-1β、TNF-α、IL-6水平及AT1R蛋白表达和PI3K、Akt、mTOR磷酸化水平依次降低（P<0.05），HDL水平、细胞自噬率、LC3-Ⅱ和Beclin 1蛋白表达水平显著升高（P<0.05）；缬沙坦高剂量组与阳性对照组大鼠各项指标差异无统计学意义。结论 缬沙坦可能通过下调AT1R/PI3K/AKT/mTOR信号通路，提高LC3-Ⅱ和Beclin 1自噬相关蛋白表达水平，促进颈动脉粥样硬化大鼠血管内皮细胞自噬，减轻炎症反应。

Objective To investigate the effects of valsartan on angiotensin Ⅱ type 1 receptor (AT1R)/phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway and the autophagy of vascular endothelial cells in carotid atherosclerosis rats. Methods The rat models of carotid atherosclerosis were established by high-fat diet combined with carotid balloon injury. The rats were randomly divided into model group (normal saline), low (10 mg/kg), medium (20 mg/kg), high (30 mg/kg) valsartan groups and positive control group (atorvastatin, 2.5 mg/kg), the sham operated rats were taken as the control group (normal saline), with 15 in each group, the drug was given by intragastric administration once a day for 4 weeks, with a volume of 10 mL/kg. At 24 hours after the last administration, the blood lipid levels of rats in each group were detected by automatic biochemical analyzer, including total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C). The levels of interleukin-6 (IL-6), interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) were detected by enzyme-linked immunosorbent assay (ELISA). Hematoxylin eosin (HE) staining was used to observe the pathological changes of carotid artery endothelium. The autophagy rate of carotid artery endothelial cells was detected by MDC staining. Western blotting was used to detect the expression levels of autophagy marker proteins LC3-Ⅱ, Beclin 1, AT1R and phosphorylation levels of PI3K, Akt and mTOR. Results Compared with those in the control group, the endothelial cells of carotid artery in the model group were disorderly arranged, the endothelium was damaged and a large number of inflammatory factors were infiltrated, and TC, TG, LDL-C, IL-1β, TNF-α, IL-6 levels, AT1R protein expression and PI3K, Akt, mTOR phosphorylation levels were significantly higher (P<0.05), HDL-C level, autophagy rate, LC3-Ⅱ and Beclin 1 protein expression levels were significantly lower (P<0.05). Compared with those in the model group, the intima of carotid artery in the low, medium and high dose valsartan groups gradually smoothed, and the infiltration of inflammatory factors decreased in turn. TC, TG, LDL-C, IL-1β, TNF-α, IL-6 levels, AT1R protein expression and PI3K, Akt, mTOR phosphorylation levels decreased in turn (P<0.05). HDL level, autophagy rate, LC3-Ⅱ and Beclin 1 protein expression levels were significantly higher (P<0.05). There was no significant difference between the high dose valsartan group and the positive control group. Conclusions Valsartan may increase the expression levels of LC3-Ⅱ and Beclin 1 autophagy related proteins by down-regulating AT1R/PI3K/Akt/mTOR signaling pathway, promote the autophagy of vascular endothelial cells in carotid atherosclerosis rats, and reduce the inflammatory reaction.

R966

河南省医药卫生计划项目（182102310159）