Kuyama H, Kitaoka T, Fujita K, Nagao S
Department of Neurological Surgery, Kagawa Medical School, Japan.
Acta Neurochir Suppl (Wien). 1994;60:325-8. doi: 10.1007/978-3-7091-9334-1_87.
We investigated the immediate effect of tris (hydroxymethyl) aminomethane (THAM) and NaHCO3 on focal cerebral ischemia produced by occlusion of the left middle cerebral artery (MCA) in cats. The animals were divided into three groups. In the control group, physiological saline was infused continuously. The THAM and NaHCO3 groups received continuous administration of 0.3 mol THAM and 7% NaHCO3, respectively, to normalize arterial pH. Local CBF measured in the marginal and suprasylvian gyri decreased less than 30 ml/100 g/min after the MCA occlusion and there were no significant differences among the three groups. Extracellular pH of the marginal gyrus (peri-infarct zone) decreased from 7.21 to 6.86 in the control group. However, extracellular pH did not show significant changes in the THAM and NaHCO3 groups. Intracellular pH of the infarct area decreased from 7.23 to 6.13 in the control group within 6 hours after occlusion. THAM had a tendency to normalize intracellular pH compared with that in the control and NaHCO3 groups. THAM significantly (p < 0.05) decreased water content of the gray matter in the marginal gyrus at 6 hours after occlusion and the infarct size compared with those in the control and NaHCO3 groups. Therefore, normalization of systemic and perifocal acidosis with THAM is effective for reducing cortical edema and infarct size in the early stage of focal cerebral ischemia probably due to the improvement of intracellular acidosis.
我们研究了三（羟甲基）氨基甲烷（THAM）和碳酸氢钠对猫左侧大脑中动脉（MCA）闭塞所致局灶性脑缺血的即时影响。将动物分为三组。对照组持续输注生理盐水。THAM组和碳酸氢钠组分别持续给予0.3 mol THAM和7%碳酸氢钠以使动脉pH值正常化。MCA闭塞后，在缘回和颞上回测量的局部脑血流量（CBF）下降至低于30 ml/100 g/min，三组之间无显著差异。对照组缘回（梗死周边区）的细胞外pH值从7.21降至6.86。然而，THAM组和碳酸氢钠组的细胞外pH值未显示出显著变化。闭塞后6小时内，对照组梗死区域的细胞内pH值从7.23降至6.13。与对照组和碳酸氢钠组相比，THAM有使细胞内pH值正常化的趋势。与对照组和碳酸氢钠组相比，THAM在闭塞后6小时显著（p < 0.05）降低了缘回灰质的含水量和梗死面积。因此，用THAM使全身和病灶周围酸中毒正常化对于在局灶性脑缺血早期减轻皮质水肿和梗死面积是有效的，这可能是由于细胞内酸中毒得到改善。
