Sinomenine protects against ischemic injury in rat hippocampal neurons

Aim To observe the neuroprotective effect of sinomenine on hippocampal neurons from injury induced by oxygen glucose deprivation( OGD) and its underlying mechanism. Methods Hippocampal neurons were exposed to OGD for 4 h followed by 24 h reoxygenation( OGD-R). Then cell viability was detected by MTT. LDH release was detected by LDH kit. Cell apoptosis was detected by Hoechst stain. The expression of Bax,Bcl-2 and caspase-3 were detected by Western blot. [Ca2 +]iof hippocampal neurons was detected by calcium imaging. Acid-sensing ion channels( ASICs) current was detected by patch clamp technique. Results SN increased cell viability and reduced LDH release. SN also inhibited neuron apoptosis and increased ratio of Bcl-2 / Bax and reduced the expression of caspase-3. OGD-induced increase of [Ca2 +]iwas inhibited by SN. Furthermore,SN inhibited ASIC1a current and also inhibited OGD induced increase of ASICs current in hippocampal neurons. Conclusion SN protects hippocampal neurons against OGD-R-induced injury. The inhibitory effect of SN on ASIC1a and calcium overload was involved in the protective effect of SN.