RESUMEN
Aim To investigate the effect of intracerebroventricular morphine postconditioning against ischemia-reperfusion injury in rat heart and the mechanism of the central nervous system opioid receptor.Methods Forty-two Sprague-Dawley Rats were established intracerebroventricular catheter placement and myocardial ischemia/reperfusion models and randomly assigned to 7 groups:Sham group(Sham),control group(CON),intravenous control group(VCON),morphine postconditioning group(POC),intracereborventricular morphine postconditioning group(MOC).According to the dosage of intracerebroventricular morphine(3 ?g?kg-1,0.3 ?g?kg-1,0.03 ?g?kg-1),MOC group was assigned to three groups :MOC 1,MOC 2,MOC 3.Infarct size(IS),a percentage of the area at risk(AAR) was determined by triphenyltetrazolium(TTC) staining.c-fos expression in nucleus of tractus solitarius was determined by immunohistochemical method and Cardiac TroponinI(cTnI) of serum was observed at 120 min of reperfusion.Results Compared with control group,IS,IS/AAR and cTnI were significantly reduced in POC and MOC groups(P0.05).c-fos expression in nucleus of tractus solitarius were significantly reduced in MOC 2,POC(P