目的 評估早期再灌流（Reperfusion）對局部缺血性腦中風（ischemic stroke）模型中電生理學上的好處。 方法 大鼠分別接受了中大腦動脈（MCA）30分鐘暫時性阻塞（第一組， n=8）或90分鐘暫時性阻塞（第二組， n=8），以及遠端中大腦動脈永久性電燒灼（thermocoagulation） （第三組， n=6）。 結果 在局部腦缺血之前，各組之體感覺誘發電位（Somatosensory evoked potentials, SSEPs）皆相當穩定。在局部缺血7天後，第三組同側（缺血側）及對側（正常側）之體感覺誘發電位減少最多，而對側體感覺誘發電位減少即為電生理官能聯繫不良之表現。第一組與第二組（暫時性缺血組）之體感覺誘發電位在兩側也都有減少的情形。隨著缺血時間越久，腦梗塞的範圍便越大，神經行為學上的損害越嚴重，而且同側及對側的體感覺誘發電位減少也越多。 討論 我們認為，早期再灌流可以促進同側及對側電位場上的恢復，這跟腦部受傷後的神經重塑過程可能非常相關。我們也發現對側電生理官能聯繫不良可以因為早期再灌流而大量減少，而且它跟髓質（striatum）的受損範圍大小是無關的。

Objectives
We evaluated electrophysiological benefits of reperfusion following ischemic stroke.
Methods Rats received either transient occlusion of the right middle cerebral artery
(MCA) for 30 (Group I, n=8) or 90 min (Group II, n=8), or permanent thermocoagulation
of the distal MCA (Group III, n=6). Results Before ischemia, stable somatosensory
evoked potentials (SSEPs) were consistently recorded. At 7 days postinsult, Group III
(permanent occlusion) had greatest reductions in the SSEPs recorded ipsilaterally and
contralaterally. Group I and Group II (transient ischemic groups) also had depressant
SSEPs recorded from the ipsilateral ischemic and the contralateral, intact brain
(electrophysiological diaschisis). However, prolonged ischemia resulted in greater brain
infarction and increased neurologic deficits in addition to greater reductions in the
ipsilateral and the contralateral SSEPs. Discussion We concluded that early reperfusion
facilitates the electrophysiological recovery in both ipsilateral lesional and the
contralateral, intact brain, which may be closely relevant to post-injury brain rewiring.
We also demonstrated that contralateral electrophysiological diaschisis could be greatly
reversed by early reperfusion and is independent of the lesion size of striatum.

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