Study Of Reduced Glutathione On Degraded Brain Injuried And Intercellular Adhesion Molecule-1 Expression After Cerebral Focal Ischemia Reperfusion In Rats

Objective: The study was to observe the effect of Reduced Glutathione(GSH)on intercellular adhesion molecule-1(ICAM-1) protein and ultrastructure in brain after focal cerebral ischemia-reperfusion in rats by peritoneal injection GSH.Methods: Male Sprague-Dawley rats were divided randomly into three groups,sham-operated(S-O)(n=15),ischemia-reperfusion(I-R)(n=15) and I-R treated with GSH(I-R+GSH)(n=15).I-R models induced by middle cerebral artery occlusion performed with thread inserted for 2-hours ischemia following 24-hour reperfusion.The neurological defective scores and brain infarct region were evaluated after operation.The number of neutrophil infiltration in ischemic areas was counted with hematoxylin-eosin staining and the ICAM-1 immunoreactive(ir) molecule was tested by immunohistochemistry.Morphocytology and ultrastructure of cerebral cortex were observed under light microscope and electron microscope.Results: 1 Compared with the S-O group:the I-R group and the I-R+GSH group havedifferent extent neurological deficit,moreover the I-R+GSH group(2.29±0.49) has improvement of neurological function in comparison with the I-R group (3.00±0.57,P <0.05);The infarctvolume of the I-R+GSH group (24.75±2.19 ) was smaller than that of the I-R group(27.08±2.31,P <0.05) .2 The ICAM-1-ir was increase after 2-hour ischemia and 24-hourreperfusion in rats.The brown ICAM-1-ir were observed in capillary wall of infarct region. The ICAM-1-ir of the I-R group and the I-R+GSH group were increase in comparison with the S-Ogroup(0.20±0.06,P <0.05).The I-R+GSH group (14.50±1.85) was lower than the I-R group (16.88±2.53, P <0.05) .3 Under light microscope,The neurons in the S-O group wereunchanged.There was no infiltration of neutrophil in brain;in the I-R group there were obvious infarction.The cortex located the ischemia region of right brain were edematous significantly in the I-R group.The circumference of neurons and micrangiums were enlarged.There were thrombosis in vessels and large neurons died in cortex and striatum,moreover a lot of neutrophil were observed in infarct region;In the I-R+GSH group there were also infarction.But the region of infarction were smaller than I-R group,and cerebral edema and infiltration of neutrophil werelight than the I-R group.4 Under electron microscope, the neurons in the S-0 group werenormal while neuron injury in the I-R group group was remarkable,but the injury in theI-R+GSH group group was obviously improved.Conclusion: The results suggest that GSH may improve neurological deficit score anddecrease infarct volume and reduce expression of ICAM-1 and restrain the infiltration ofneutrophil so as to relieve inflammation after focal cerebral ischemia reperfusion in rats,andplay an neuroprotective effect against middle cerebral artery occulusion.