摘要
目的探讨慢性心肌缺血时，心肌葡萄糖、脂肪酸代谢相关酶mRNA和蛋白表达的变化以及与心肌存活的关系。方法采用14头中华实验猪，制成慢性缺血模型，测定心肌葡萄糖转运蛋白（Glut）1和4、链乙酰辅酶-A-脱氢酶、心脏脂肪酸结合蛋白（H-FABP）等基因mRNA的表达量，以及Glutl和Glut4的表达。结果与对照区比较，缺血区mRNA表达明显增加的基因有Glutl（5854±5287比9466±9033，P=0．043）和Glut4（34188±44714比60398±64699，P=0．043）：mRNA表达明显降低的基因有H-FABP（50718±62412比18123±15925，P=0．043）；与对照区比较，梗死区mRNA表达明显降低的基因有H-FABP（87545±92990比21919±15224，P=0．043）；存活节段心肌的Glutl基因表达高于不存活节段心肌的Glutl基因表达（19794±20454比5134±6022，P=0．046）。结论在慢性缺血时，心肌葡萄糖代谢相关酶mRNA及蛋白的增加与糖代谢增强有密切的关系，对心肌细胞抵抗缺血有积极的作用。
Objective To investigate the changes myocardial enzymes related to glycolysis and fatty acid metabolism in chronic myocardial ischemia and to evaluate the relationship between the gene expression of glycolytic metabolism related enzymes and myocardial viability. Methods Fourteen Chinese experimental pigs underwent placement of arterial ring into the left anterior descending coronary artery so as to establish models of myocardial ischemia and infarction, 18F-2-deoxy-2-fluoro-D-glucose single photon emission computed tomography was conducted to observe the viability of the myocardium. One week later the pigs were killed with their hearts taken out. Specimens of ischemic zone, infarction zone, and non-ischemic zone were obtained. RT-PCR was used to detect the mRNA expression of glucose transporter （GLUT） 1, GLUT4, medium-chain acyl-CoA dehydrogenase （MCAD）, and heart-fatty acid binding protein （H-FABP）. Immunohistochemistry was used to examine the protein expression of Glutl and Glut4. Periodic Acid Schiffhematoxylin staining was conducted to detect the glycogen. Results Pathological examination showed 5 pigs with myocardial infarction and 5 pigs with ischemia In the pigs with ischemia, the mRNA expression levels of GLUT1 and GLUT4 in the ischemic zone were 9466 ± 9033 and 60 398 ± 64 699 respectively, both significantly higher than those in the control zone （5854 ± 5287 and 34 188 ±44 714 respectively, P = 0.043, P = 0.043） . the RNA expression of H-FABP in the ischemic zone was 18 123 ± 15 925, significantly lower than that in the control zone （50 718± 62 412, P = 0. 043 ） , and there was no significant difference in the mRNA expression level of MCAD. In the pigs with infarction the mRNA expression of level of H-FABP in the infarction zone was 21 919± 15 224, significantly lower than that in the control zone （87 545± 92 990, P = 0. 043 ） , and there were not significant differences in the mRNA expression levels of the GLUT1, GLUT4, and MCAD genes （all P 〉 0.05）. The mRNA expression of GLUT1 in the myocardial segments with perfusion/metabolism mismatch was significantly higher than that in the myocardial segments with perfusion/metabolism match （19 794 20 454 vs 5134 ± 6022, P = 0. 046）. The ischemic cardiac myocytes showed hypertrophy and positive staining of anti-GLUT1 polyclonal antibody. Conclusion The changes of mRNA and protein expression of enzymes related to glycolysis and fatty acid metabolism after myocardial ischemia play an important role in glycolytic metabolism during myocardial ischemia.
出处
《中华医学杂志》
CAS
CSCD
北大核心
2008年第31期2209-2213,共5页
National Medical Journal of China
基金
北京市自然科学基金资助项目（7053072）
关键词
心肌缺血
代谢疾病
葡萄糖代谢
脂肪酸类
Myocardial ischemia
Metabolism diseases
Glucose
Fatty acids metabolism
