Effects of sevoflurane on voltage-gated sodium channel Na(v)1.8, Na(v)1.7, and Na(v)1.4 expressed in Xenopus oocytes.

Sevoflurane is widely used as a volatile anesthetic in clinical practice. However, its mechanism is still unclear. Recently, it has been reported that voltage-gated sodium channels have important roles in anesthetic mechanisms. Much attention has been paid to the effects of sevoflurane on voltage-dependent sodium channels. To elucidate this, we examined the effects of sevoflurane on Na(v) 1.8, Na(v) 1.4, and Na(v) 1.7 expressed in Xenopus oocytes. The effects of sevoflurane on Na(v) 1.8, Na(v) 1.4, and Na(v) 1.7 sodium channels were studied by an electrophysiology method using whole-cell, two-electrode voltage-clamp techniques in Xenopus oocytes. Sevoflurane at 1.0 mM inhibited the voltage-gated sodium channels Na(v)1.8, Na(v)1.4, and Na(v)1.7, but sevoflurane (0.5 mM) had little effect. This inhibitory effect of 1 mM sevoflurane was completely abolished by pretreatment with protein kinase C (PKC) inhibitor, bisindolylmaleimide I. Sevoflurane appears to have inhibitory effects on Na(v)1.8, Na(v)1.4, and Na(v) 1.7 by PKC pathways. However, these sodium channels might not be related to the clinical anesthetic effects of sevoflurane.