Little J R, Cook A, Cook S A, MacIntyre W J
Stroke. 1981 Mar-Apr;12(2):218-93. doi: 10.1161/01.str.12.2.218.
The objectives were to study plasma and erythrocyte flow in an area of acute focal cerebral ischemia and define their relationship to developing microcirculatory obstruction as determined by morphological techniques. Eighteen adult cats, anesthetized with ketamine hydrochloride, had right middle cerebral artery (MCA) occlusion. Plasma flow was determined by measuring the transit of Iodine-131 (131I) albumin and erythrocyte flow was determined by measuring the transit of Technetium-99 (99Tc) labeled erythrocytes in the right Sylvian region. Transit studies were performed before and immediately after right MCA occlusion and at the end of the ischemic period, 1 hour, 3 hours, or 6 hours after occlusion. Intra-arterial perfusion with a buffered formaldehyde - colloidal carbon solution was carried out after completion of the isotope studies. Swelling of cerebral tissue and impaired carbon filling in the right MCA territory were seen initially after 3 hours occlusion and were more severe after 6 hours occlusion. Ischemic neuronal alterations, edema formation, and capillary luminal narrowing increased with longer periods of occlusion. 131I albumin transit time in the right Sylvian region was 8 +/- 2 seconds before occlusion and 10 +/- 2 seconds immediately after occlusion. 99Tc erythrocyte transit time was 10 +/- 2 seconds before occlusion and 12 +/- 3 seconds immediately after occlusion. 99Tc erythrocyte transit time was 10 +/- 2 seconds before occlusion and 12 +/- 3 seconds immediately after occlusion. Transit times increased progressively with longer periods of occlusion in cats developing cortical ischemic changes. No evidence of complete microcirculatory obstruction to albumin and erythrocyte transit was seen in cats with 6 hours of occlusion despite the impaired filling of the cortical microcirculation with carbon. There were no findings to substantiate the hypothesis that plasmapheresis develops during the early phases of cerebral infarction.
研究目的是探讨急性局灶性脑缺血区域的血浆和红细胞流动情况，并确定它们与形态学技术所确定的微循环阻塞发展之间的关系。18只成年猫用盐酸氯胺酮麻醉后，进行右侧大脑中动脉（MCA）闭塞。通过测量碘-131（131I）白蛋白的通过情况来测定血浆流动，通过测量锝-99（99Tc）标记红细胞在右侧西尔维安区域的通过情况来测定红细胞流动。在右侧MCA闭塞前、闭塞后立即以及缺血期结束时（闭塞后1小时、3小时或6小时）进行通过研究。在同位素研究完成后，用缓冲甲醛-胶体碳溶液进行动脉内灌注。闭塞3小时后最初可见右侧MCA区域脑组织肿胀和碳填充受损，闭塞6小时后更严重。随着闭塞时间延长，缺血性神经元改变、水肿形成和毛细血管腔狭窄加重。闭塞前右侧西尔维安区域131I白蛋白通过时间为8±2秒，闭塞后立即为10±2秒。99Tc红细胞通过时间闭塞前为10±2秒，闭塞后立即为12±3秒。在出现皮质缺血改变的猫中，随着闭塞时间延长，通过时间逐渐增加。尽管皮质微循环的碳填充受损，但在闭塞6小时的猫中未发现白蛋白和红细胞通过完全微循环阻塞的证据。没有发现支持脑梗死早期发生血浆置换这一假说的证据。
