Abstract: Objective To observe the effect of renal denervation (RDN) on the cardiac oxidative stress and sympathetic nerve remodeling after myocardial infarction (MI) in canine. Methods Canine (n=18) were randomly divided into three groups: Sham operation group (SHAM group, n=6), MI group (n=6), MI+RDN group (n=6). Anterior myocardial infarction was gained by gelatin sponge embolization of the left anterior descending artery. At four weeks post-MI, left ventricular enddiastolic volume (LVEDV), left ventricular end-systolic volume (LVESV) and left ventricular ejection fraction (LVEF) were examined using echocardiography. Immunohistochemical assay was used to analyze the distribution and density of tyrosine hydroxylase (TH) stained nerve fibers at peri-infarct zone. Myocardial superoxide dismutase (SOD) activity and malondialde⁃ hyde (MDA) were also assessed. Results Compared with dogs in SHAM group, LVEF and SOD expression were decreased in MI group and MI+RDN group (P＜0.05), but Left ventricular end diastolic pressure (LVEDP), LVEDV, LVESV, MDA and rate of TH positive staining nerve fibers were increased (P＜0.05). There was a negative correlation between the rate of TH positive staining nerve fibers and SOD level (rs=-0.818，P＜0.05) and a positive correlation between rate of TH positive stain⁃ ing nerve fibers with MDA level (rs=0.900，P＜0.05). By contract, compared with MI group, LVEF and SOD in MI +RDN group were increased (P＜0.05), while LVEDV, LVESV, MDA and rate of TH positive staining nerve fibers were significant⁃ ly lowered (P＜0.05). Conclusion RDN is effective to decrease the level of cardiac oxidative stress and improve cardiac sympathetic nerve remodeling and heart function after myocardial infarction in canine.

Key words: renal denervation, myocardial infarction, sympathetic nerve remodeling, oxidative stress, animals, laboratory