Gasbarrini A, Pasini P, Nardo B, De Notariis S, Simoncini M, Cavallari A, Roda E, Bernardi M, Roda A
Patologia Medica, Catholic University of Roma, Italy.
Free Radic Biol Med. 1998 Jan 15;24(2):211-6. doi: 10.1016/s0891-5849(97)00056-7.
Oxygen free radicals generation is a major cause of liver injury during reperfusion. Luminescence analysis has been recently proposed to measure free radical generation by isolated cells or organs, but it allows only global tissue luminescence. Using a special Saticon videocamera with image intensifier we aimed to visualize and localize oxygen free radical generation in isolated perfused livers exposed to an oxydative stress. Livers isolated from rats aged 4 and 30 months were exposed to ischemia/reperfusion; photons emission by the organs was continuously recorded. Lucigenin was utilized as a chemiluminigenic probe to assess superoxide anion generation. In both groups, chemiluminescence was not detectable during ischemia, while it was observed after reperfusion. Photons emission started after few minutes of reperfusion, was maximal after 15-20 min and disappeared within 50-60 min. Chemiluminescence emitted by livers from younger rats however, was significantly higher when compared to chemiluminescence emitted by organs isolated from old rats (0.8 +/- 0.1 vs 0.44 +/- 0.08 photons x 10(5)/s, respectively, after 15 min; p < .01). The superimposition of chemiluminescent and live image permitted to determine the regional production rate and distribution of photons. In conclusion, the age of the rats influences significantly the amount of oxyradicals produced in the liver during post-ischemic reperfusion. The method described, allowing the visualization in real time of oxygen free radicals generation on the surface of isolated intact organs, represents a novel and potent tool for the study of oxidative stress.
氧自由基的产生是再灌注期间肝损伤的主要原因。最近有人提出用发光分析来测量分离的细胞或器官产生的自由基，但它只能检测组织整体的发光情况。我们使用一台配有图像增强器的特殊硒砷碲（Saticon）摄像机，旨在可视化和定位暴露于氧化应激的离体灌注肝脏中氧自由基的产生。从4个月和30个月大的大鼠分离出的肝脏进行缺血/再灌注处理；持续记录器官发出的光子。利用光泽精作为化学发光探针来评估超氧阴离子的产生。在两组中，缺血期间均未检测到化学发光，而再灌注后可观察到。光子发射在再灌注几分钟后开始，15 - 20分钟后达到最大值，并在50 - 60分钟内消失。然而，与从老年大鼠分离的器官发出的化学发光相比，幼年大鼠肝脏发出的化学发光明显更高（再灌注15分钟后分别为0.8±0.1和0.44±0.08个光子×10⁵/秒；p <.01）。化学发光图像与实时图像叠加，可确定光子的区域产生速率和分布。总之，大鼠的年龄对缺血后再灌注期间肝脏中产生的氧自由基量有显著影响。所描述的方法能够实时可视化分离的完整器官表面氧自由基的产生，是研究氧化应激的一种新颖且有效的工具。
