Activation of microglia in rat model of epilepsy during persistent state and analysis of temporal and spatial expression of different types of microglia

Objective To investigate the activation of microglia in state of continuity (SE) of epileptic rat model and the temporal and spatial expression of different types of microglia. Methods 60 healthy male Wistar rats were randomly divided into control group, SE at the beginning (NC group), SE lasting for 30 minutes (SE30min group), SE lasting for 1 hour (SE1h group), SE holding. For 2 hours (SE2h), 12 rats in each group. Behavioral changes and activation of microglia in hippocampus were observed. The expression levels of IL-6, IL-1beta and IL-10 and IL-4 were detected. Results In the SE group, with the prolongation of time, the response of MG cells increased, and the activation of MG cells was most obvious in SE2h group. The expression levels of IL-10, IL-4 protein and mRNA in SE1h group and SE2h group were significantly higher than those in NC group and SE30min group, while the expression levels of IL-6, IL-1beta protein and mRNA in M1 group were significantly lower than those in NC group and SE30min group (P<0.05). Conclusion Activation of microglia can be seen in pilocarpine-induced epilepsy rat model. With the prolongation of seizure time, polarization of microglia gradually transforms into neurotrophic M2 cells. The expression levels of anti-inflammatory factors IL-10 and IL-4 will increase, while the expression of pro-inflammatory factors IL-6 and IL-1beta will decrease. Key words: Status epilepticus; Microglia; Cell polarization; Classical activation; Alternative activation