【摘要】 目的:探讨雾化吸入硝酸甘油(NTG)对新生猪急性低氧性肺动脉高压和心肌损害的疗效和安全性。方法:24头上海种新生白猪建立急性低氧性肺动脉高压和心肌损害的模型。将动物随机分成4组:sham组(假手术组);model组(模型组);N1组(缺氧结束后雾化吸入NTG 0.5 h)和N2组(缺氧状态0.5 h后即雾化吸入NTG 0.5 h)。实验过程中连续监测平均动脉压(MAP)和平均肺动脉压(MPAP),间断监测血清肌酸激酶心肌同功酶(CK-MB)、肌钙蛋白I(cTnI)浓度,TUNEL法检测心肌细胞凋亡,免疫组化染色检测心肌组织肌红蛋白(Mb)及心肌细胞缝隙连接蛋白Cx43的含量。结果:缺氧1 h后,N2组的MPAP显著低于model组(P<0.01);缺氧结束后0.5 h,N1组的MPAP显著低于model组(P<0.05)。4组新生猪在相同时点的MAP差异无统计学意义(P>0.05)。缺氧结束后5 h,N1和N2组的CK-MB与model组差异无统计学意义(P>0.05);N1和N2组的cTnI的含量均显著低于model组(P<0.01)。N1和N2组的心肌细胞凋亡指数显著少于model组(P<0.05);心肌Mb在N1和N2组的表达显著强于model组(P<0.01);心肌Cx43在N1和N2组的表达也显著强于model组(P<0.05)。结论:缺氧同时或缺氧后雾化吸入NTG均能选择性地降低急性低氧引起的肺动脉高压,对心肌也有一定的保护作用。更多还原

【Abstract】 AIM: To investigate the effects of nebulized nitroglycerin(NTG) on pulmonary,systemic hemodynamics and myocardial impairment during pulmonary hypertension induced by hypoxia in piglets.METHODS: Twenty-four piglets(5-7 days old) were randomly divided into four groups: ① sham group;② model group;③ NTG1 group;④ NTG2 group.Mean artery pressure(MAP) and mean pulmonary artery pressure(MPAP) were monitored continuously.Serum CK-MB and cTnI were measured intermittently.Apoptotic cells were detected with TUNEL method.Myoglobin(Mb) and connexin 43(Cx43) staining were studied by immunohistochemistry.RESULTS: After nebulization,MPAP in NTG1 group and NTG2 group were significantly lower than that in model group(P<0.05 and P<0.01,respectively).Five hours after hypoxia,serum cTnI in NTG1 group and NTG2 group were both significantly lower than that in model group(P<0.01).The percentage of apoptotic cells in NTG2 group was significantly lower than that in model group(P<0.05).Immunohistochemistry method results showed that the expression of Mb and Cx43 in NTG1 group and NTG2 group were both significantly stronger than those in model group(P<0.01 and P<0.05,respectively).CONCLUSION: NTG nebulization produces a selective pulmonary vasodilation either during or after the exposure of hypoxia and improves myocardial impairment in acute hypoxic newborn piglets.更多还原