Postconditioning with vagal stimulation attenuates local and systemic inflammatory responses to myocardial ischemia reperfusion injury in rats

To assess effects of postconditioning with the vagal stimulation (VS) on the local and systematic inflammatory responses to acute myocardial ischemia reperfusion injury (IRI). Sixty male Sprague-Dawley rats were randomly allocated into three groups: sham group, ischemia reperfusion group (IR group), and postconditioning with the VS group (POVS group). Serum levels of inflammatory cytokines during reperfusion and myocardial levels of inflammatory cytokines in both ischemic and non-ischemic regions at the end of the experiment were assayed. The infarct size was assessed by Evans blue and triphenyltetrazolium chloride staining. The infarct size was significantly reduced in the POVS group compared to the IR group. Serum levels of TNF-alpha at 30, 60, and 120 min of reperfusion and serum levels of HMGB-1, ICAM-1, IL-1, and IL-6 at 120 min of reperfusion were significantly lower in the POVS group than in the IR group. Myocardial levels of TNF-alpha, HMGB-1, ICAM-1, IL-1, and IL-6 in both ischemic and non-ischemic regions were also significantly reduced in the POVS group compared with the IR group. Postconditioning with the VS can significantly attenuate the local and systemic inflammatory responses to myocardial IRI, and provide an obvious cardioprotection.