Effect of sevoflurane preconditioning on expression of metabotropic glutamate receptor type II during focal cerebral ischemia-reperfusion in rats

Abstract

Objective To evaluate the effect of sevoflurane preconditioning on the expression of metabotropic glutamate receptor type Ⅱ (mGluRⅡ) during focal cerebral ischemia-reperfusion (I/R) in rats. Methods Forty-eight clean-grade healthy male Sprague-Dawley rats were divided into 3 groups (n=16 each) using a random number table method: sham operation group (group S), cerebral I/R group (group I/R) and sevoflurane preconditioning group (group Sev). Rats were anesthetized with 10% chloral hydrate 3 ml/kg.Focal cerebral I/R was produced by occlusion of the right middle cerebral artery for 2 h followed by 24 h reperfusion.In group Sev, 2.7% sevoflurane was inhaled for 1 h and 24 h later focal cerebral I/R was produced.At 24 h after reperfusion, neurological deficit was scored, the cerebral infarct size was determined by TTC staining, the cell apoptosis in ischemic penumbra was observed by TUNEL, IκB-α expression was detected by Western blot, and mGluRⅡexpression was determined by immunofluorescent staining.The apoptosis rate was calculated. Results Compared with group S, the neurological deficit score, cerebral infarct size and apoptosis rate were significantly increased, the expression of mGluRⅡwas up-regulated, and the expression of IκB-α was down-regulated in I/R and Sev groups (P<0.05). Compared with group I/R, the neurological deficit score, cerebral infarct size and apoptosis rate were significantly decreased, the expression of mGluRⅡwas down-regulated, and the expression of IκB-α was up-regulated in group Sev (P<0.05). Conclusion Sevoflurane preconditioning reduces focal cerebral I/R injury through inhibiting the expression of mGluRⅡ in rats. Key words: Anesthetics, inhalation; Ischemic preconditioning; Brain; Reperfusion injury; Receptors, glutamate