大鼠肺吞噬细胞释放自由基在放射性肺炎发展中的作用

Effect of free radicals released from pulmonary alveolar phagocytes on development of radiation pneumonia in rats

６０Ｃｏγ射线（２０Ｇｙ）照射大鼠胸部，以支气管－肺泡冲洗液细胞（ＢＡＬＦＣ）的化学发光作为吞噬细胞释放自由基的指标，用肺组织羟脯氨酸含量评价肺纤维细胞增殖程度，观察照后０．５，１和２个月时肺吞噬细胞释放自由基的变化及其与肺组织纤维细胞增殖性病变的可能关联。结果表明：随照后时间延长，ＢＡＬＦＣ数增加；ＢＡＬＦＣ化学发光的本底值降低，激活值增高；肺组织湿重增加，羟脯氨酸含量增高。这些损伤性变化在补硒后表现出明显的减轻或恢复性转变。进一步分析表明：照后ＢＡＬＦＣ在肺内聚集及其释放自由基的增高与肺纤维细胞增殖有一定的关联，提示肺内吞噬细胞释放的自由基可能是放射性肺炎病变发生发展的一个重要因素。

Measuring the hydroxylproline(HyP) content in rat lungs and the chemiluminescence(CL) of bronchus alveolar lavage fluid cell (BALFC) at 0.5,1 and 2 months after irradiation with 60Co γ-rays respectively, we found that the amount of BALFC and its CL stimulated by zymosan and the pulmonary HyP content were apparently increased after irradiation,and these alternations took a favourable turn when selenium was supplemented to irradiated rats,suggesting that selenium protected the rats from radiation injury of lung. In addition,we found that there were certain interrelations between the multiplication of pulmonary fibrocytes and the free radicals released from accumulated BALFC in pulmonary alveoli,indicating that the free radicals produced from alveolar phagocytes may be an important factor in development of rat radiation pneumonia.