[Sevoflurane preconditioning induced delayed neuroprotection against focal cerebral ischemia in rats].

OBJECTIVE: To investigate whether the reactive oxygen species (ROS) and mitochondrial ATP-sensitive potassium (mitoKATP) channels were involved in delayed neuroprotection induced by sevoflurane on tumor necrosis factor-alpha (TNF-alpha) and interleukin-1beta (IL-1beta) levels.

METHODS: Eighty-four male SD rats weighing 250 approximately 280 g, undergoing thread embolism of the right middle cerebral artery occlusion (MCAO) to cause focal ischemia for 2 h and then undergoing 24 h reperfusion, were randomly divided into 7 groups (n=12, each): a sham group(S), an ischemia-reperfusion group (I/R), a sevoflurane preconditioning group (Sevo), a 2-mercaptopropionylglycine (ROS scavenger)+sevoflurane group (MPG+Sevo), a 5-hydroxydecanoate (a mitoK(ATP) blocker) + sevoflurane group (5-HD+Sevo), an MPG group, and a 5-HD group. The protein level of TNF-alpha and IL-1beta in the cerebral issue was detected by enzyme linked immunosorbent assay (ELISA) and the expression of mRNA was measured by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR).

RESULTS: Apoptosis index (AI), the protein level and the mRNA expression of TNF-alpha and IL-1beta were significantly higher in the I/R group than those of Group S. Pre-administration of sevoflurane could inhibit the increase of the protein level and the expression of mRNA of TNF-alpha, and IL-1beta and attenuate the cerebral damage induced by ischemia-reperfusion. Neuroprotection of sevoflurane preconditioning was abolished by MPG and 5-HD. However, MPG and 5-HD alone had no effect.

CONCLUSION: Sevoflurane can produce delayed protection against cerebral ischemia-reperfusion injury by down-regulating TNF-alpha, IL-1beta protein, and mRNA expression.