TRPC通道对PC12细胞缺氧缺糖再灌注后氧化损伤的保护作用

瞬时受体电位C通道(transient receptor potential canonical,TRPC)属于瞬时受体电位（TRP）离子通道家族成员之一，与Ca2+ 调控及氧化应激关系密切．然而，TRPC通道在缺血缺氧性脑损伤中的作用仍有争议．本实验采用MTT法、台盼蓝排斥实验、LDH漏出实验联合Annexin/PI染色流式分析等显示，当采用通道阻断剂-SKF96365特异阻断TRPC通道时，PC12细胞对缺氧缺糖再灌注（oxygen-glucose deprivation／reperfusion，OGD-R）引起的损伤变得更敏感，细胞凋亡增加．尽管同时采用SKF96365、NMDA受体、AMPA受体和L-型钙通道阻断剂可引起细胞损伤和死亡减弱，但仍呈现明显的SKF96365浓度依懒性，提示TRPC通道参与细胞对缺氧缺糖再灌注耐受的调节，具有保护作用．钙指示剂Fluo-3AM荧光标记结合激光共聚焦显微镜分析显示，SKF96365可明显降低缺氧缺糖再灌注后细胞内的Ca2+浓度．总之，实验结果提示，TRPC通道对缺氧缺糖再灌注引起的细胞损伤和凋亡具有保护作用，其机制可能涉及TRPC通道对细胞内钙浓度的调节，详尽机制有待进一步研究．

Protective of Transient Receptor Potential Canonical (TRPC) onOxygen-Glucose Deprivation/Reperfusion (OGD-R)-induced Injury in PC12 Cells

The transient receptor potential canonical (TRPC) is a subfamily of transient receptor potential (TRP) permeable to Ca2+，which is closely related to Ca2+ regulation and oxidative stress．However，the role of TRPC in hypoxic ischemic brain damage is still controversial．Our data imply that TRPC can protect the PC12 cells from the injury induced by oxygen-glucose deprivation／reperfusion(OGD-R)．The MTT assay，trypan blue exclusion，lactate dehydrogenase (LDH) release，Annexin/PI(AV/PI) dye showed that PC12 cells became more sensitive of OGD-R induced injury，and obviously increased of cell apoptosis after treated with TRPC blocker SKF96365．Even though PC12 cells injury, cell death were weakened using the NMDA receptor blocker，calcium channel blocker and AMPA-receptor blocker. These changes were still reflected in SKF96365 dose-dependent manner．The dada showed that TRPC had protective action on the regulation of resist OGD-R．The calcium indicator Fluo-3 AM in combination with laser confocal microscopy showed that SKF96365 could obviously reduced the intracellular Ca2+ after OGD-R. In conclusion，TRPC can protect the PC12 cells from OGD-R and that the mechanism may be related to the regulation of intracellular free calcium concentration，and the detailed mechanism needs further research．