Abstract 2317: Nociceptive Stimulation: A Novel Cardioprotective Strategy
Recent studies show that electro-stimulation from upper extremities or spinal cord elicits cardioprotective effects against I/R injury. In previous studies, we have identified a novel cardioprotective phenomenon that occurs subsequent to remote trauma (abdominal skin incision), termed RPCT. The purpose of this study was to determine whether an abdominal nociceptive stimulation (ANS), either by electrical or by chemical stimulation of remote peripheral sensory nerves along the same area of skin incision can produce cardioprotection similar to that of RPCT against MI. An in vivo mouse I/R model was used. ANS was performed 15 minutes prior to I/R or at the beginning of reperfusion with the needles placed along the line of abdominal incision. Infarct size was used to evaluate the results of I/R injury (45 min coronary occlusion, 24h reperfusion) with or without prior ANS treatments. Histological, immunochemical, cellular and functional studies were performed at appropriate timepoints. The results of demonstrate that both pre and post-conditioning produce an 85% reduction in infarct size (6.3 ± 2.2 vs. 52.6 ± 2.8 in preconditioning, P < 0.01; 10.6 ± 3.1 vs. 60.2 ± 3.8 in post-conditioning, P < 0.01, n = 6). Hematoxylin and Eosin staining showed that there was decreased infiltration after ANS compared to sham. We further show that ANS-preconditioning reduces apoptosis as evidenced by TUNEL staining and DNA fragmentation and reduces post-ischemic ventricular dysfunction. In conclusion, our results support 1) ANS is as protective as early phase of RPCT and 2) ANS elicited pre- and post-conditioning provides cardioprotection against myocardial infarction and dysfunction, at least in part, by reducing cardiomyocyte apoptosis after I/R. These results may suggest a novel therapeutic strategy for cardioprotection against I/R injury and have important implications for surgical patients at risk for myocardial infarction.