The neuroprotective effect of NBQX on oligodendrocyte precursor cells in rat cerebral cortex after whole brain irradiation

Objective: To explore the early phase radioresponse of oligodendrocyte precursor cells in rat-cerebral cortex after whole brain irradiation and the protective effect of MK801 and NBQX. Methods: MK801 (5 mmol/L) or NBQX(50 mmol/L) was injected into the cerebral cortex of SD rats by using a stereo-directional instrument after whole brain irradiation at dose of 10 Gy. Then NG2 and O4-positive cells in the cortex were determined at each time-point by immunofluorescence histochemistry. Results: The numbers of NG2 and O4-positive cells in the cortex of rats in the irradiation group increased significantly on day 7 after irradiation as compared with those in the sham irradiation group (P<0.05). There was no obvious difference for the number of NG2 or O4-positive cells in the cortex between rats of the MK801 group and the irradiation group (P>0.05). The numbers of NG2 and O4-positive cells in the cortex of rats in the NBQX group were significanctly higher on days 1 and 7 than that those of rats in the irradiation group (P<0.05). Conclusion: The number of oligodendrocyte precursor cells in the cortex of rats increases reactively in the early phase after whole brain irradiation and has alteration with observing time-point. And NBQX has some neuroprotective effect on oligodendrocyte precursor cells in the early phase of radiation injury. (authors)