Effects of repetitive transcranial magnetic stimulation on adenosine triphosphate content and microtubule associated protein-2 expression after cerebral ischemia-reperfusion injury in rat brain / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Repetitive transcranial magnetic stimulation (rTMS) research has mainly been focused on the therapeutic effect of psychiatric disorders and Parkinson's disease. A few studies have shown that rTMS might protect against delayed neuronal death induced by transient ischemia, enhance long-term potentiation in ischemic conditions and affect regional brain blood flow and metabolism. The aim of this study was to determine the effects of repetitive transcranial magnetic stimulation (rTMS) on adenosine triphosphate (ATP) content and microtubule associated protein-2 (MAP-2) expression in rat brain after middle cerebral artery occlusion (MCAO)/reperfusion.</p><p><b>METHODS</b>To study the effects of different timecourses of rTMS on ATP content and MAP-2 expression, 90 rats were randomly divided into three groups (30 rats in each group). To study the effects of multiple rTMS parameters on ATP content and MAP-2 expression, the rats in each group were further divided into six subgroups (five rats each). The rats were sacrificed at 1-hour, 24-hour and 48-hour intervals after reperfusion, and the brain tissues were collected for the detection of ATP and MAP-2.</p><p><b>RESULTS</b>rTMS could significantly increase ATP content and MAP-2 expression in the left brain following ischemic insult (P < 0.01) and different rTMS parameters had different effects on the ATP level and the MAP-2 expression in the left striatum. A high-frequency rTMS played an important role in MAP-2 expression and ATP preservation.</p><p><b>CONCLUSIONS</b>This study revealed that rTMS induced significant increase of ATP content and MAP-2 expression in the injured area of the brain, suggesting that the regulation of both ATP and MAP-2 may be involved in the biological mechanism of the effect of rTMS on neural recovery. Therefore, rTMS may become a potential adjunctive therapy for ischemic cerebrovascular disease.</p>

Effects of transcranial magnetic stimulation on motor cortical excitability and neurofunction after cerebral ischemia-reperfusion injury in rats / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To clarify the effects of repetitive transcranial magnetic stimulation (rTMS) on rat motor cortical excitability and neurofunction after cerebral ischemia-reperfusion injury.</p><p><b>METHODS</b>After determined awake resting motor threshold (MT) and motor evoked potentials (MEPs) of right hindlimbs, 20 Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) reperfusion injury, then rTMS were applied to rTMS group (n=10) at different time, while control group (n=10) received no stimulation. A week later, MT and MEPs were evaluated again, as well as neurological deficits and infarct volume. The effects of rTMS and MCAO reperfusion injury on these parameters were analyzed.</p><p><b>RESULTS</b>After MCAO reperfusion, both MT level and neurological deficit scores increased, distinct focal infarction formed, and latency of MEP elongated. Compared with the control group, the increased extent of MT and neurological scores of rats receiving rTMS were significantly lower (P < 0.05), as well as the infarct volumes reduced significantly (P < 0.05). But MEP was not affected by rTMS obviously. There was a positive linear correlation between postinjury MT and infarct volume (r = 0.64, P < 0.05).</p><p><b>CONCLUSION</b>rTMS may facilitate neurofunction recovery after cerebral ischemia-reperfusion. Postinjury MT could provide prognostic information after MCAO reperfusion injury.</p>