Anwar M, Weiss H R
Department of Physiology Biophysics University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School, Piscataway 08854.
Am J Physiol. 1989 Nov;257(5 Pt 2):H1656-62. doi: 10.1152/ajpheart.1989.257.5.H1656.
The effects of adenosine on regional cerebral blood flow and indexes of the total and perfused microvascular bed were studied after 1 h of middle cerebral artery occlusion in the anesthetized rat. Iodo[14C]antipyrine was used to determine cerebral blood flow. Fluorescein isothiocyanate-dextran was used to study the perfused microvasculature, and an alkaline phosphatase stain was used to identify the total bed. Mean arterial blood pressure was significantly reduced by adenosine. Cerebral blood flow increased significantly by 75%, except in the flow-restricted cortex where flow averaged 28 +/- 15 (SD) ml.min-1.100 g-1 in control and 34 +/- 33 ml.min-1.100 g-1 in adenosine-treated animals. No significant regional structural differences were observed within the microvascular beds of the two groups. The percentage of the microvascular volume perfused increased significantly in all brain regions in the adenosine-treated rats, including the flow-restricted cortex. The percent perfused arteriolar volume in the flow-restricted cortex was 30 +/- 12% in control and 95 +/- 3% in adenosine-treated animals. Similar values for the capillary bed were 22 +/- 10% in control and 54 +/- 3% in adenosine-treated rats. These results indicate a maintenance of flow with a reduction in diffusion distances in the flow-restricted cortex after treatment with adenosine.
在麻醉大鼠大脑中动脉闭塞1小时后，研究了腺苷对局部脑血流量以及总微血管床和灌注微血管床指标的影响。使用碘[14C]安替比林测定脑血流量。使用异硫氰酸荧光素 - 葡聚糖研究灌注的微血管系统，并使用碱性磷酸酶染色来识别总微血管床。腺苷使平均动脉血压显著降低。脑血流量显著增加了75%，但在血流受限的皮质区域除外，该区域在对照组中的血流量平均为28±15（标准差）ml·min-1·100g-1，在腺苷处理组动物中为34±33ml·min-1·100g-1。两组微血管床内未观察到明显的区域结构差异。在腺苷处理的大鼠中，所有脑区包括血流受限的皮质区域，灌注的微血管体积百分比均显著增加。在血流受限的皮质区域，对照组中灌注的小动脉体积百分比为30±12%，腺苷处理组动物中为95±3%。毛细血管床的类似值在对照组中为22±10%，在腺苷处理的大鼠中为54±3%。这些结果表明，腺苷处理后，血流受限的皮质区域在维持血流的同时扩散距离缩短。
