Abstract: AIM: To investigate the changes of intracellular calcium concentration in vital brain slices after pretreatment with isoflurane in cerebral ischemic reperfusion rats.METHODS: Focal cerebral ischemia was induced by inserting a suture into the middle cerebral artery of rats.Reperfusion was accomplished by withdrawing the suture after 2 hours'ischemia.The changes of intracellular calcium in vital brain slices were determined by fluorescent Ca²⁺-indicator fluo-3 AM.The effects of isoflurane pretreatment were evaluated before cerebral ischemia on the intracellular calcium of cortex and striatum.RESULTS: Intracellular calcium concentration increased significantly both in the cortex and the striatum of the brain after cerebral ischemia reperfusion.Isoflurane pretreatment given before cerebral ischemia inhibited the elevation of Ca²⁺in the cortex but not in the striatum induced by ischemia reperfusion injury.CONCLUSION: Isoflurane can inhibit Ca²⁺overloading in cortex induced by cerebral ischemia reperfusion, which may be one of the mechanisms of isoflurane neuroprotection.

Key words: isoflurane, preconditioning, calcium, cerebral ischemia, laser confocal scanning microscope