title: Vagus nerve stimulation reduces infarct size in rat focal cerebral ischemia: an unlikely role for cerebral blood flow.
abstract: We sought to investigate the effect of cervical vagus nerve stimulation (VNS) on cerebral blood flow (CBF), infarct volume, and clinical outcome in a model of middle cerebral artery occlusion in rats. Electrical stimulation of the right and left vagus nerves was initiated 30min after the induction of the right-sided ischemia and lasted for 1h. Infarct size measurement revealed that the volume of ischemic damage was 41-45% smaller in animals receiving stimulation as compared with control animals. Both the right and left VNS caused subtle reduction in CBF during each 30-s stimulation period that quickly returned back to the baseline level at the end of each stimulation cycle. There was no significant effect of VNS on CBF during the entire 1-h stimulation period. The effect of VNS on tissue outcome was associated with better neurological outcome at both 1- and 3-day time points after the induction of ischemia. These findings suggest that VNS-induced protection against acute ischemic brain injury is not primarily mediated by changes in CBF, stimulation of both the right and left nerve have comparable effects, and VNS is effective after ipsilateral and contralateral focal ischemia.
authors: MGH/MIT/HMS A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital-East, 149 13th Street, Charlestown, MA O2129, USA. iay@partners.org
authors: Ilknur
authors: I
authors: Ay
authors: A Gregory
authors: AG
authors: Sorensen
authors: Hakan
authors: H
authors: Ay
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D002544:Cerebral Infarction / Q000209:etiology* / Q000628:therapy*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D004195:Disease Models, Animal; D007839:Functional Laterality; D006339:Heart Rate / Q000502:physiology; D020244:Infarction, Middle Cerebral Artery / Q000150:complications*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D016896:Treatment Outcome; D055536:Vagus Nerve Stimulation / Q000379:methods*