| Background and purpose:The appropriate methods of prevention and therapy for cerebral ischemia to restore the function of damaged neurons as well as to reduce disability and mortality remain a subject of debate.The cerebral edema on acute stage after ischemia is both the main secondary lesions and the important causes of death. How to control the developing of ischemic edema represents the main target of acute stroke therapy.On the other hand,more and more neurologists confirmed that the plasticity of the brain had played an important role during the rehabilitation period and the treatment for enhancing the plasticity of the brain have been the attention focus for a long time.Repetitive transcranial magnetic stimulation(rTMS) which occurred in the last decade can affect the functional state of the local stimulus and remote sites.It has been a routine treatment alternative for the major depression or some dyskinesia diseases,but it is still on an investigation stage about whether rTMS could affect the pathophysiological conditions of ischemic stroke.So,one of the aim of this study is mainly to investigate the effect of rTMS on the ischemic cerebral edema and the expression of AQP4 at the acute stage of middle cerebral artery occlusion and reperfusion injury.Another aim is to investigate the possible effect of rTMS on the plasticity of the brain.Methods:Established the SD rat MCA cerebral ischemia-reperfusion model with suture occlusion technique according to modified Zea Longa method and then the rats were devide into four therapy groups.Different rTMS were applied to them right after the reperfusion was performed and once a day during the next 7 days followed.Sham-rTMS and sham-operating group were set as the control group.At 6h,12h and 24 h after the reperfusion,the neurological impairment evaluation score of a part of rats were recorded and then were killed to measure the water content of the brain and the protein AQP4 levels by immunohistochemistry and Western blot technology,the extent of neurological deficits graded as scores of other rats were evaluated every other day and then were killed at the 7d after the reperfusion to measure the protein GAP-43and SYN levels by immunohistochemistry and Western blot technology. Changes in these parameters and effects of rTMS on these parameters were analyzed.Results:The results showed that ischemia reperfusion injury produced distinct focal infarction,neurological deficits,different degree of cerebral edema and there is a highly mortality in 24h after the injury,rTMS could lower the death rate,reduce ischemic cerebral edema and decrease the expression of the protein AQP4 of the rats at the acute stage of ischemia stroke.The effect of rTMS group with high frequency and high intensity was statistically better than the sham-rTMS group(P＜0.05). rTMS continuously could improve rehabilitation of neurofunction and the expression of the protein GAP-43and SYN.The effect of rTMS group with high frequency and high intensity was statistically better than the sham- rTMS group(P＜0.05).Conclusion:The application of rTMS could lower the death rate of the acute stage of ischemia stroke.The application of rTMS could reduce ischemic cerebral edema and decrease the expression of the protein AQP4.The application of rTMS continuously could improve rehabilitation of neurofunction.The application of rTMS continuously could enhance the expression of the protein GAP-43and SYN.The rTMS group with high frequency and high intensity show a superiority effect than other groups.
|
PDF Full Text Request