Effects of 20 Hz repetitive transcranial magnetic stimulation with different intensities on neurobehavior and glial fibrillary acidic protein in rats with cerebral infarction / 中华物理医学与康复杂志

ABSTRACT

Objective To investigate the effects of 20 Hz repetitive transcranial magnetic stimulation (rTMS) with different intensities on neurobehavior and expression of glial fibrillary acidic protein (GFAP) in ischemic penumbra of rats with cerebral infarction,so as to explore the probable mechanism. Methods Forty-three rats were randomly divided into a blank control group( n =7 ),a model control group( n =7),a sham stimulation control group(n =8) and a rTMS group (n =21) ; the rTMS group was further subdivided into 3 subgroups80％ MT subgroup,100％ MT subgroup and 120％ MT subgroup,with 7 rats in each subgroup.The cerebral infarction model was established by right middle cerebral artery occlusion (MCAO) in each group except the blank control group.The 3 rTMS subgroups were given 14 successive blocks of 20 Hz rTMS with corresponding intensity.The sham stimulation control group received sham treatment (without any output).The model control group was given no stimulation,and the blank control group did not receive any special treatment.Functional assessments were performed at 3 different time points.After 14-day treatment,the expression of GFAP proteins in ischemic penumbra were detected by immunohistochemistry technique. Results Functional outcome reflected from 3 behavioral tests in 100％ MT subgroup after 14-day stimulation was better than 1 day after operation,while in the other rTMS subgroups functional outcomes were just better in 2 behavioral tests.The expressions of GFAP in 3 rTMS subgroups were all less than that in model control group. Conclusions The 20 Hz rTMS with 80％ MT and 100％ MT might be safe and effective to improve the functional outcome in rats with acute cerebral infarction,especially 100％ MT.Decrease of expression of GFAP in ischemic penumbra might be one of the mechanisms of beneficial effects of rTMS in ischemia brain injury.