Research On The Effect Of CX3CR1 On Microglia In Experimental Ischemic Mice

ObjectiveTo explore the changes of morphology and number of the lesion area microglia at different time points in cerebral ischemia reperfusion in mice, to investigate the effect of CX3CR1 on microglia.Methods1. The 25 wild-type (Wild-type, WT) C57BL/6 mice were randomly divided into: 6h group,12h group,24h group,48h group,72h group,N= 5, To establish cerebral ischemia-reperfusion models.2. After ischemia-reperfusion surgery, the experimental animals were neurological deficit scored.In the 6h,12h,24h,48h,72h after surgery, these mice were sacrificed and perfused, brains were removed, the brain tissues were paraffin-embedded sections,sections were HE stained, to measure the infarct area;By immunohistochemistry paraffin sections were anti-Ibal (microglia/macrophages) staining,to observe infarct cortex, penumbra, striatum, hippocampus 4 regional and contralateral same site;to calculate the number of microglia each side, and observe the morphology of microglia.3. Select the infarct size and the largest number of microglia time group for WT mice and CX3CR1 knockout (Knock-out, KO) C57BL/6 mice were compared, analyzed infarction area and the number of microglia.Results1. WT mice’s neurological deficit scores from postoperative recovery,6h,12h,24h, 48h,72h were gradually increased.2. By HE staining, these models were proven to be successful; on the time axis 6h,12h,24h,48h,72h,WT mice’infarct areas were gradually increasing;6h,12h,24h significant difference (P<0.05) after statistical analysis,24h,48h,72h no significant difference (P> 0.05).In 72h, WT mice’infarct areas were more larger than KO mice’, and there was a statistically significant difference (P<0.05).3. The number of microglia WT mice infarct was more than the contralateral side, and there was a statistically significant difference (P<0.05).The number of microglial cells in WT mice infarct side was gradually increased, except between 48h and 72h group, the remaining differenced statistical analysis significantly in each group (P<0.05).WT mice’infarction side of microglia amoeba-like changes were significantly at 12h,24h,48h,72h.In 72h, the number of microglia in cerebral side WT mice was more than KO mice, and there was a statistically significant difference (P<0.05).Conclusion1. on the time axis 6h,12h,24h,48h,72h,the number of microglia on infarction side were gradually increased, and the infarct size and neurological deficit scores were positively correlated in WT mice.2. Early in ischemia-reperfusion, CX3CR1 signaling deficiency could reduce the number of microglia and cerebral infarct size in ischemia-reperfusion mice.3. Early in ischemia-reperfusion, inhibition of CX3CR1 signaling had led to protect nerve function,could be used as treatment for cerebral ischemia.