実験的脳虚血に対する蛋白分解酵素阻害剤ulinastatinの効果

Effect of Ulinastatin on Postischemic Brain Edema in Cats

　ネコ中大脳動脈閉塞，再開通モデルを用いて局所脳血流量，脳比重を測定し，ulinastatinの脳浮腫に対する作用を検討した。

　雑種成ネコをコントロール群6頭，uhnastatin投与群7頭に分け，経眼窩的に左中大脳動脈に達し，2時間閉塞により局所脳虚血を作成した。再開通2時間後にネコを屠殺し，microgravimetry法によって局所脳比重を測定した。なお中大脳動脈閉塞および再開通時の局所脳血流量の測定は，水素クリアランス法によって行った。

　Ulinastatin投与群では，コントロール群に比べて，虚血，再開通後の脳比重は有意に高く，ulinastatinの抗脳浮腫作用を表すものと考えられた。

The effect of ulinastatin on postischemic brain edema was investigated in adult mongrel cats. Focal brain ischemia was produced by occlusion of the left middle cerebral artery (MCA) through the transorbital approach. Following two hours of occlusion, the brain was reperfused for two hours. In all seven animals of the ulinastatin-treated group, ulinastatin was administered intravenously at a dose of 50000 U/kg before and after occlusion. In the control group, six animals were given only vehicle. Measurements of regional cerebral blood flow (rCBF) were performed before MCA occlusion by the hydrogen clearance method, and then repeated every 30 minutes during and after occlu-sion. Following two-hour reperfusion, the animals were sacrificed by intravenous KC1 injection. Specific gravity of the cortex, where rCBF was measured, was determined by microgravimetric method.

In the analysis of specific gravity of the cortex, in which mean rCBF during ischemia was above 15ml/100 g/min, no significant difference was found between the ulinastatin-treated and control groups. In the specimen with mean rCBF below 15ml/100g/ min during ischemia, cortical specific gravity was reduced remarkably in the control group, while not decreased in the ulinastatin-treated group. The difference was statistically significant between two groups (p＜0.001). These findings suggest antiedema effect of ulinastatin.