高原环境诱发大鼠心血管损伤的评估：临床和灌注指标的综合分析

Assessment of Cardiovascular Injury Induced by Plateau Environment in Rats: A Comprehensive Analysis of Clinical and Perfusion Indices

摘要: 目的：研究高海拔暴露对大鼠血液指标、心肌酶谱、心肌灌注、肺动脉压和免疫组化的影响。方法：平原组(四川成都，海拔约500米) 20只大鼠饲养至4周龄，之后将10只大鼠转移运至青海玛多(海拔4200 m)动物实验室饲养24周。24周后，比较两组大鼠的血液指标、心肌酶谱、心肌灌注、肺动脉压和免疫组化的差异。结果：在血液指标中观察到显著差异，高海拔组RBC、HGB、HCT、MCV、ALT、Cr和TC水平高于平原组(P < 0.05)。此外，AST、LDH和CK在内的心肌酶谱指数在高海拔组显著升高(P < 0.05)。在心肌灌注参数方面，与平原组相比，高海拔组的MBF值较低，而TTP、MTT指标显著增高(P < 0.05)。高海拔组PA水平高于平原组(P < 0.05)。高海拔组大鼠心肌有明显的病理变化，包括心肌细胞排列紊乱、空泡变性。免疫组织化学标记物HIF-2α和VEGF在高海拔组的表达显著高于平原组(P < 0.05)。结论：这项研究表明，暴露在高海拔地区会导致大鼠血液指数、心脏酶谱、心肌灌注、肺动脉压和免疫组织化学的显著变化，并且心肌会受到一定损伤。这些发现表明，高海拔环境会对身体的各个系统产生深远的生理影响。

Abstract: Objective: To study the effects of high altitude exposure on blood indices, cardiac enzyme profile, myocardial perfusion, pulmonary artery pressure and immunohistochemistry in rats. Methods: Twenty rats in the plain group (Chengdu, Sichuan Province, about 500 m above sea level) were reared until 4 weeks of age, after which 10 rats were transferred and transported to the animal laboratory in Mado, Qinghai Province (4200 m above sea level) for 24 weeks. After 24 weeks, the differences in blood indices, cardiac enzyme profiles, myocardial perfusion, pulmonary artery pressure, and immunohistochemistry were compared between the two groups of rats. Results: Significant differences were observed in blood indices, with higher levels of RBC, HGB, HCT, MCV, ALT, Cr and TC in the high altitude group than in the plains group (P < 0.05). In addition, myocardial enzyme profile indices including AST, LDH and CK were significantly higher in the high altitude group (P < 0.05). In terms of myocardial perfusion parameters, MBF values were lower in the high altitude group compared with the plain group, while TTP and MTT indices were significantly higher (P < 0.05). PA levels were higher in the high altitude group than in the plain group (P < 0.05). There were obvious pathological changes in the myocardium of rats in the high altitude group, including disturbed arrangement of cardiomyocytes and vacuolar degeneration. The expression of immunohistochemical markers HIF-2α and VEGF was significantly higher in the high altitude group than in the plains group (P < 0.05). Conclusion: This study demonstrates that exposure to high altitude leads to significant changes in blood indices, cardiac enzyme profiles, myocardial perfusion, pulmonary artery pressure, and immunohistochemistry, and that the myocardium is subjected to some damage in rats. These findings suggest that high altitude environments can have profound physiological effects on various body systems.