ABSTRACT
ObjectiveTo investigate the effects of emulsified isoflurane preconditioning on the expression of platelet-activating factor (PAF) and PAF receptor during focal cerebral ischemia-reperfusion (I/R) in rats.MethodsThirty-two healthy adult male SD rats weighing 250-300 g were randomly divided into 4 groups ( n =8each):group sham operation (group S); group I/R; group emulsified isoflurane preconditioning( group EI) and group lipid emulsion (group LE).Focal cerebral I/R was induced by 2 h occlusion of middle cerebral artery followed by reperfusion in groups I/R,EI and LE.8％ emulsified isoflurane 10.5 ml/kg and 30％ lipid emulsion 10.5 ml/kg were injected intraperitoneally at 24 h before cerebral ischemia in groups EI and LE respectively.The neurologic deficit score (NDS) (0 =no deficit,4 =unable to control) was evaluated at 12 h of reperfusion.Venous blood samples were collected for measurement of plasma PAF concentration.The animals were then sacrificed and their brains removed for determination of infarct size (by TTC staining) and PAF receptor expression in hippocampus and cerebral cortex (by Western blot).ResultsFocal cerebral I/R significantly increased NDS,the infarct size,plasma PAF concentration and PAF receptor expression in cerebral cortex and hippocampus in group I/R as compared with group S.Emulsified isoflurane preconditioning significantly attenuated the focal cerebral I/R induced above changes in group EI as compared with group I/R,but there was no significant difference between groups I/R and LE.ConclusionEmulsified isoflurane preconditioning can attenuate focal cerebral I/R injury by inhibiting PAF and PAF receptor expression.
ABSTRACT
Objective To investigate the effect of emulsified isoflurane preconditioning on postsynaptic density protein 95 (PSD95) activation in brain during focal cerebral ischemia-reperfusion (I/R)injury in rats.Methods Thirty-two pathogen-free male SD rats weighing 280-300 g were randomly divided into 4 groups (n =8each): sham operation group(group S),group I/R,emulsified isoflurane group(group EI) and lipid emulsion group(group LE).Focal cerebral I/R was induced by middle cerebral artery occlusion for 2 h followed by reperfusion.8％ emulsified isoflurane 10.5 ml/mg or 30％ lipid emulsion 10.5 ml/mg was injected intraperitoneally at 24h before I/R in groups EI and LE respectively.The neurologic deficit score (NDS) was evaluated at 6 h of reperfusion and then 4 rats were sacrificed,and brains were removed for determination of phosphorylatied PSD95 (pPSD95) expression in ischemia cortex and hippocampus by Western blot.Four rats were sacrificed at 24 h of reperfusion and then their brains were removed for determination of infarct volume percentage.Results NDS,infarct volume percentage and pPSD95 expression in ischemia cortex and hippocampus were higher in groups I/R,EI and LE than in group S( P ＜ 0.01 ).NDS,infarct volume percentage and pPSD95 expression in ischemia cortex and hippocampus were lower in group EI than in group I/R( P ＜ 0.05).There was no significant difference in NDS,infarct volume percentage and pPSD95 expression between groups I/R and LE(P ＞ 0.05).Conclusion Emulsified isoflurane preconditioning can attenuate focal cerebral I/R injury in rats by inhibiting PSD95 activation in brain.