Zhang X M, Ellis E F
Department of Pharmacology and Toxicology, Medical College of Virginia, Virginia Commonwealth University, Richmond 23298-0613.
Am J Physiol. 1990 Aug;259(2 Pt 2):H497-503. doi: 10.1152/ajpheart.1990.259.2.H497.
These studies determined whether superoxide dismutase (SOD), an oxygen free-radical scavenger, affects brain and lung vascular protein extravasation and water content after acute hypertension. Hypertensive vascular injury was induced in rats by bolus injection of norepinephrine. Vascular permeability was assessed with 125I-labeled serum albumin and water content determined by wet and dry weight measurement. Pretreatment with SOD prevented or reduced the increase in brain water content and brain and lung protein extravasation caused by hypertension, whereas inactivated SOD had no effect. SOD also reduced mortality caused by acute hypertension. Treatment 30 min after hypertension with SOD or polyethylene glycol-conjugated SOD reduced edema caused by hypertension. In some instances SOD reduced tissue water content and permeability to below normal control levels found in animals without hypertension. These studies show that oxygen radicals contribute to increases in permeability and water content after hypertensive injury and also suggest that oxygen radicals may contribute to regulation of vascular permeability and water content in normal animals.
这些研究确定了超氧化物歧化酶（SOD），一种氧自由基清除剂，是否会影响急性高血压后大脑和肺部血管的蛋白质渗出及含水量。通过静脉注射去甲肾上腺素诱导大鼠发生高血压性血管损伤。用125I标记的血清白蛋白评估血管通透性，通过湿重和干重测量确定含水量。用SOD预处理可预防或减轻高血压所致的脑含水量增加以及脑和肺蛋白质渗出，而失活的SOD则无此作用。SOD还降低了急性高血压所致的死亡率。高血压发生30分钟后用SOD或聚乙二醇结合的SOD进行治疗可减轻高血压所致的水肿。在某些情况下，SOD可使组织含水量和通透性降低至无高血压动物的正常对照水平以下。这些研究表明，氧自由基会导致高血压损伤后通透性和含水量增加，还提示氧自由基可能参与正常动物血管通透性和含水量的调节。
