Bus J S, Vinegar A, Brooks S M
Am Rev Respir Dis. 1978 Sep;118(3):573-80. doi: 10.1164/arrd.1978.118.3.573.
The purpose of this study was to examine the in vivo effects of acute exposure to a cadmium chloride aerosol on the activity of pulmonary enzymes and selected physiologic parameters that are altered by exposure to oxidant agents. Male rats were exposed for 1 hour to 0.5 per cent aerosol of cadmium chloride. At 1,5, and 11 days after exposure to cadmium chloride, exposed rats compared to control rats (data expressed as per cent of control values) had lung-to-body weight ratios of 192, 174, and 140 per cent; lung glucose-6-phosphate dehydrogenase activities of 90, 107, and 135 per cent; lung superoxide dismutase activities of 96, 101, and 132 per cent; tidal volumes of 62, 63, and 89 per cent; respiratory frequencies of 170, 145, and 108 per cent; and lung weight-specific static deflation volumes at 30 cm water of 30, 13, and 31 per cent. A zero-order clearance of cadmium from whole lung was observed, with a half-time of 27.4 days. Light microscopic examination of lung tissue revealed initial pulmonary edema on day 1 that progressed to interstitial pneumonitis on day 5, with some recovery by 11 days after exposure. The cadmium induced biochemical, physiologic, and pathologic alterations were similar to the responses observed in lungs of rats exposed to a wide variety of pulmonary irritants; thus, the changes observed may represent a nonspecific response to tissue injury.
本研究的目的是检测急性暴露于氯化镉气雾剂对肺酶活性及某些因暴露于氧化剂而改变的生理参数的体内效应。雄性大鼠暴露于0.5%的氯化镉气雾剂中1小时。在暴露于氯化镉后的第1、5和11天，与对照大鼠相比（数据以对照值的百分比表示），暴露组大鼠的肺与体重比分别为192%、174%和140%；肺葡萄糖-6-磷酸脱氢酶活性分别为90%、107%和135%；肺超氧化物歧化酶活性分别为96%、101%和132%；潮气量分别为62%、63%和89%；呼吸频率分别为170%、145%和108%；在30厘米水柱压力下的肺重量特异性静态呼气末容积分别为30%、13%和31%。观察到镉从全肺的清除呈零级动力学，半衰期为27.4天。肺组织的光镜检查显示，第1天出现初始肺水肿，第5天进展为间质性肺炎，暴露后11天有所恢复。镉诱导的生化、生理和病理改变与暴露于多种肺部刺激物的大鼠肺中观察到的反应相似；因此，观察到的变化可能代表对组织损伤的非特异性反应。
