OBJECTIVETo study whether the analgesis of oxymatrine (OMT) affects N-type voltage-gated calcium channels (VGCCs).

METHODSTotally 45 mice were randomly divided into the sham-operation group, the model group [established by partial sciatic nerve ligation (PSNL)] , and the OMT treatment group according to random digit table, 15 in each group. The dorsal root ganglions (DRG) were separated in PSNL pain model mice. Intracellular calcium concentration ([Ca2+]i) was determined with Fluo-3 AM immunofluorescent probe in cultured DRG neurons. Different protein expression levels of N-type (Cav2. 2) and L-type ( Cav1. 3) among VGCCs from brain and DRG tissues were detected with Western blot.

RESULTSCompared with the sham-operation group, [Ca2+]i, increased in cultured DRG neurons (P <0. 05) , protein expression levels of Cav2. 2 in the brain tissue increased (P <0. 05), protein expression levels of Cav2. 2 in DRG tissues decreased in the model group (P <0. 01). Compared with the model group, [Ca2+]i, decreased in cultured DRG neurons (P < 0. 05), protein expression levels of Cav2. 2 in the brain tissue decreased (P <0. 01), protein expression levels of Cav2. 2 in DRG tissues increased in the OMT treatment group (P <0. 01). There was no statistical difference in Cav1. 3 expressions in cultured DRG neurons and the brain (P >0. 05).

CONCLUSIONAnalgesic effect of OMT might be related to Cav2. 2 channel mediated calcium ion flux.