大黄对大鼠冠脉血栓形成的影响及其机制

Effects of Rhubarb on the form of coronary artery blood clots in rats and underlying mechanism

目的观察大黄对大鼠冠脉血栓形成的影响并探讨其机制。方法取50只经适应性喂养后的Sprague-Dawley（SD）大鼠随机分为对照组、模型组、大黄治疗组（低、中、高剂量组），每组10只，大黄治疗组（低、中、高剂量组分别为50、100、200 mg/kg），大黄治疗组按照剂量给药，对照组及模型组给予同等体积的生理盐水，连续喂养7d。除对照组外，均用含三氯化铁（FeCl3）溶液的滤纸条建立大鼠冠脉血栓模型。苏木素-伊红（HE）染色法观察大鼠冠脉组织病理改变；流式细胞术检测P-选择素（CD62P）水平改变；反转录-聚合酶链反应（RT-PCR）法测定凋亡相关基因半胱氨酰天冬氨酸特异性蛋白酶（Caspase）-3及Caspase-8 mRNA表达水平的变化。结果与模型组比较，大黄各剂量组均在一定程度上改善了血管内壁状态，大黄高剂量组效果最为明显；大黄低中高剂量组CD62P荧光强度分别为783.2±53.3、596.7±37.5、385.7±31.2，模型组为1 067.4±143.8，低剂量组与模型组比较（t＝5.902，P＝0.000），中高剂量组与模型组比较（t＝10.105、14.765，P均＝0.000）；大黄低中高剂量组及模型组Caspase-3 mRNA相对表达量分别为（51.04±5.15）%、（44.74±4.06）%、（37.13±3.66）%、（73.88±6.73）%，（t＝8.464、11.685、15.079）。大黄低中高剂量组及模型组Caspase-8 mRNA相对表达量分别为（47.69±4.61）%、（41.52±3.72）%、（34.96±3.63）%、（67.83±6.08）%，（t＝8.377、11.708、14.794）。低中高剂量组与模型组组间差异均有统计学意义（P均＝0.000）。结论大黄对模型大鼠血栓形成具有较强的抑制作用，可有效降低CD62P水平及细胞凋亡基因的表达，对冠脉血栓的形成具有抑制作用。

Objective To observe the effect of rhubarb on coronary thrombosis in rats and explore its mechanism.Methods Fifty sprague-Dawley （SD） rats were randomly divided into control group, model group, rhubarb-treated group （low, medium and high dose subgroups）, 10 rats in each group. In rhubarb-treated subgroups, rhubarb （low, medium and high doses： 50, 100, 200 mg/kg） was given. The control group and model group were given the same volume of normal saline, continuously feeding for 7 days. Except for the control group, the rat model of coronary thrombosis was established with filter paper strips containing FeCl3 solution. Hematoxylin-eosin （HE） staining was used to observe the pathological changes of coronary artery in rats. The changes of P-selectin （CD62P） were detected by flow cytometry. The expression of cysteinyl aspartate-specific protease （Caspase）-3 and Caspase-8 mRNA was determined by reverse transcription-polymerase chain reaction （RT-PCR）.Results As compared with the model group, rhubarb in each dose subgroup improved the state of vascular wall to some extent, and rhubarb in high dose group had the most obvious effect. The fluorescence intensity of CD62P in different rhubarb dose subgroups （low, medium, high） and model group was 783.2±53.3, 596.7±37.5, 385.7±31.2, 1 067.4±143.8 respectively, with significant difference between low dose subgroup and model group （t=5.902, P=0.000）, or between medium and high dose subgroups with model group （t=10.105, 14.765, P=0.000）. The Caspase-3 mRNA relative expression in rhubarb subgroups and model group was （51.04±5.15）%, （44.74±4.06）%, （37.13±3.66）% and （73.88±6.73）% respectively （t=8.464, 11.685, 15.079）, and the Caspase-8 mRNA relative expression was （47.69±4.61）%, （41.52±3.72）%, （34.96±3.63）% and （67.83±6.08）% respectively （t=8.377, 11.708, 14.794）, with significant difference between model group with middle and high dose rhubarb subgroups （P=0.000）.Conclusion Rhubarb has a strong inhibitory effect on thrombosis in model rats, which can effectively reduce the level of cd62p and the expression of apoptosis gene, and inhibit the formation of coronary artery thrombosis.