Changes of nitric oxide synthesis in cardiac ischemia reperfusion injury

    TANG Xingª²San, MA Yaª²Zhen, LIU Hongª²Yun, ZHU Xiaoª²Qin, LEI Shuiª²Sheng

    1Life Science and Technology College of Xiaogan University, Xiao¬ðgan 432000, China, 2Department of Anatomy, Tongji Medical College, Huazhong University of Science and Technology, Wu¬ðhan 430030, China

    ¡¾Abstract¡¿ AIM: To investigate the expression and function of endothelial nitric oxide synthase (eNOS) and inducible NOS (iNOS) during ischemiaª²reperfusion injury (IRI) in rat hearts. METHODS: IRI was induced by clamping the left anterior descending (LAD) of coronary artery for 1h, followed by reperfusion. Nitric oxide synthase (NOS) activities of hearts was assayed at various time points and NOS protein levels as well as NOS mRNA expression were determined by Western blot and RTª²PCR methods respectively. RESULTS: eNOS activity, protein level and mRNA expression all increased after 2ª²6 h of IRI and decreased after 3 d of IRI and then gradually returned to basal level after 21 d. iNOS was expressed after 12 h of IRI and reached the peak level at day 3 after IRI and then decreased to basal level. CONCLUSION: The expression of iNOS is high while that of eNOS is low during cardiac ischemiaª²reperfusion injury. Proper regulation of eNOS and iNOS expression may be therapeutically helpful in treating patients with cardiac ischemiaª²reperfusion injury. ......