Previous studies on ectopic firing of injured nerves in the chronic constriction injury (CCI) model indicated that calcium-activated potassium channels play a key role, but the direct pharmacological evidence has not been reported. This study examined the effect of TEA and relatively specific calcium-activated potassium channel blockers IBTX and Apamin on spontaneous firing of injury nerves in CCI model rats. The results showed that both IBTX and Apamin could lead to bifurcation scenarios, indicating that the BK and SK channels are involved in the regulation of spontaneous firing of injured nerves. The results imply that calcium-activated potassium channels may exist in injured nerves in CCI model, and may be involved in regulation of spontaneous firing of injured nerves.

chronic constriction injury；ectopic firing; calcium-activated potassium channel