Objective:To investigate the potential protective effect of Shexiang Tongxin dropping pills(STDP)on ischemia-reperfusion injury and its underlying mechanisms in improving endothelial cell function in coronary microvas...Objective:To investigate the potential protective effect of Shexiang Tongxin dropping pills(STDP)on ischemia-reperfusion injury and its underlying mechanisms in improving endothelial cell function in coronary microvascular disease(CMVD).Methods:A rat model of myocardial ischemia-reperfusion injury with CMVD was established using ligation and reperfusion of the left anterior descending artery.The effect of STDP(21.6 mg/kg)on cardiac function was evaluated using echocardiography,hematoxylin-eosin staining,and Evans blue staining.The effects of STDP on the microvascular endothelial barrier were assessed based on nitric oxide production,endothelial nitric oxide synthase expression,structural variety of tight junctions(TJs),and the expression of zonula occludens-1(ZO-1),claudin-5,occludin,and vascular endothelial(VE)-cadherin proteins.The mechanisms of STDP(50 and 100 ng/mL)were evaluated by examining the expression of sphingosine 1-phosphate receptor 2(S1PR2),Ras Homolog family member A(RhoA),and Rho-associated coiled-coil-containing protein kinase(ROCK)proteins and the distribution of ZO-1,VE-cadherin,and Factin proteins in an oxygen and glucose deprivation/reoxygenation model.Results:The administration of STDP on CMVD rat model significantly improved cardiac and microvascular endothelial cell barrier functions(all P<.05).STDP enhanced the structural integrity of coronary microvascular positioning and distribution by clarifying and completing TJs and increasing the expression of ZO-1,occludin,claudin-5,and VE-cadherin in vivo(all P<.05).The S1PR2/RhoA/ROCK pathway was inhibited by STDP in vitro,leading to the regulation of endothelial cell TJs,adhesion junctions,and cytoskeletal morphology.Conclusion:STDP showed protective effects on cardiac impairment and microvascular endothelial barrier injury in CMVD model rats induced by myocardial ischemia-reperfusion injury through the modulation of the S1PR2/RhoA/ROCK pathway.展开更多
API 6A井口装置及采油树设备当应用于特殊或恶劣工况,如用于海洋钻井平台钻井作业、极地环境钻井作业及压裂增产作业时,需考虑井口装置及采油树设备的性能等级、可靠性和使用寿命等因素,确保设备在额定工作压力、额定工作温度以及高含...API 6A井口装置及采油树设备当应用于特殊或恶劣工况,如用于海洋钻井平台钻井作业、极地环境钻井作业及压裂增产作业时,需考虑井口装置及采油树设备的性能等级、可靠性和使用寿命等因素,确保设备在额定工作压力、额定工作温度以及高含硫化氢的介质下高效稳定地工作。相较于常规PR1级,API 6A规范对井口装置及采油树设备关键部件的PR2级性能测试有严格的试验程序和验收要求。文章介绍井口装置及采油树设备关键部件之一芯轴式套管悬挂器和油管悬挂器的PR2性能测试过程、方法及注意事项,供同行参考交流。展开更多
基金supported the National Natural Science Foundation of China(81930113).
文摘Objective:To investigate the potential protective effect of Shexiang Tongxin dropping pills(STDP)on ischemia-reperfusion injury and its underlying mechanisms in improving endothelial cell function in coronary microvascular disease(CMVD).Methods:A rat model of myocardial ischemia-reperfusion injury with CMVD was established using ligation and reperfusion of the left anterior descending artery.The effect of STDP(21.6 mg/kg)on cardiac function was evaluated using echocardiography,hematoxylin-eosin staining,and Evans blue staining.The effects of STDP on the microvascular endothelial barrier were assessed based on nitric oxide production,endothelial nitric oxide synthase expression,structural variety of tight junctions(TJs),and the expression of zonula occludens-1(ZO-1),claudin-5,occludin,and vascular endothelial(VE)-cadherin proteins.The mechanisms of STDP(50 and 100 ng/mL)were evaluated by examining the expression of sphingosine 1-phosphate receptor 2(S1PR2),Ras Homolog family member A(RhoA),and Rho-associated coiled-coil-containing protein kinase(ROCK)proteins and the distribution of ZO-1,VE-cadherin,and Factin proteins in an oxygen and glucose deprivation/reoxygenation model.Results:The administration of STDP on CMVD rat model significantly improved cardiac and microvascular endothelial cell barrier functions(all P<.05).STDP enhanced the structural integrity of coronary microvascular positioning and distribution by clarifying and completing TJs and increasing the expression of ZO-1,occludin,claudin-5,and VE-cadherin in vivo(all P<.05).The S1PR2/RhoA/ROCK pathway was inhibited by STDP in vitro,leading to the regulation of endothelial cell TJs,adhesion junctions,and cytoskeletal morphology.Conclusion:STDP showed protective effects on cardiac impairment and microvascular endothelial barrier injury in CMVD model rats induced by myocardial ischemia-reperfusion injury through the modulation of the S1PR2/RhoA/ROCK pathway.