Neuroprotective effect of limb ischemic post‐conditioning on focal brain ischemia/reperfusion injury in rats

Abstract

The purpose of this study was to investigate the neuroprotective effect of limb ischemic post-conditioning (LIP) on focal brain ischemia/reperfusion injury in rats. Adult male Sprague-Dawley rats were undergoing 90 min of middle cerebral artery occlusion followed by reperfusion for 22 hours. LIP was performed by occluding the unilateral or bilateral femoral arteries for 3 cycles of 10 min ischemia/10 min reperfusion at the beginning of ischemic brain reperfusion. Neurological deficits of the animals were evaluated 22 h after reperfusion, using a 6-point neurological function scoring system. The infarct size of the brain slices stained with 2,3,5-triphenyltetrazolim was determined by area analysis. Both unilateral and bilateral LIP increased the neurological scores and reduced infarct size compared with those of the rats without LIP. However, the neuroprotection of bilateral LIP was stronger than unilateral LIP. The protective effect was attenuated by removal of bilateral sciatic nerves or extracorporeal circulation of bilateral hindlimbs via femoral arteries. The results suggest that LIP can protect rats from focal brain ischemia/reperfusion injury, which is probably mediated by releasing mediators from ischemic limbs and nervous reflexes. (Supported by ZJSTB grant No.2005C30026)