Dufresne A, Sébastien P, Michaud D, Perrault G, Bégin R
School of Occupational Health, McGill University, Montréal Quebec, Canada.
Exp Lung Res. 1994 Mar-Apr;20(2):157-68. doi: 10.3109/01902149409064380.
Previous experiments with the sheep model of silicosis have demonstrated a reduction of the pathological activity of quartz after treatments with aluminum lactate (Al-lac), such as Al-lac pretreatment of intratracheally injected quartz or Al-lac inhalation of quartz-exposed animals. Preliminary data also suggested a more effective alveolar clearance of quartz treated with Al-lac. The present study was undertaken to fully document the effect of Al-lac treatments on the pulmonary retention of quartz. Sheep (on average, 27 per group) received a single injection in the tracheal lobe of either 100 mg/100 mL of alpha-quartz, 100 mg/100 mL of alpha-quartz followed by Al-lac inhalations at 1-month intervals, or 100 mg/100 mL of alpha-quartz Al-lac pretreated in vitro. Samples of lung parenchyma were analyzed at 2, 6, and 10 months after the injection. The quartz concentration in each sample was measured using the X-ray diffraction method. The concentrations were expressed in micrograms of quartz per milligram of dry lung parenchyma. The geometric mean concentrations in each of the three groups at 2 months were statistically different (ANOVA of the log values; p = .016) as well as at 6 months (ANOVA of the log values; p = .001). Al-lac clearly reduced the pulmonary retention of quartz. Both modalities of Al delivery were equally effective in clearing quartz up to 2 months, which may explain the documented reduction in pathological activities after in both forms of therapy. However, quartz soaked in Al-Lac solution was more effective than inhalation of Al-lac after quartz exposure. The half-life of both native quartz and quartz Al-lactate inhaled was 5.05 and 4.99 months, respectively, while it was 3.1 months for Al-treated quartz. Al-lac inhalations after the second month of exposure do not significantly affect the rate of clearance of deposited quartz.
先前用矽肺绵羊模型进行的实验表明，用乳酸铝（Al-lac）处理后，石英的病理活性降低，例如对气管内注射石英进行Al-lac预处理或对接触石英的动物进行Al-lac吸入。初步数据还表明，Al-lac处理的石英在肺泡中的清除更有效。本研究旨在全面记录Al-lac处理对石英肺内潴留的影响。绵羊（每组平均27只）在气管叶单次注射100 mg/100 mL的α-石英、100 mg/100 mL的α-石英，随后每隔1个月进行Al-lac吸入，或在体外进行Al-lac预处理的100 mg/100 mL的α-石英。在注射后2、6和10个月对肺实质样本进行分析。使用X射线衍射法测量每个样本中的石英浓度。浓度以每毫克干肺实质中石英的微克数表示。三组中每组在2个月时的几何平均浓度有统计学差异（对数值的方差分析；p = 0.016），在6个月时也有统计学差异（对数值的方差分析；p = 0.001）。Al-lac明显降低了石英的肺内潴留。两种Al给药方式在清除石英方面直至2个月时同样有效，这可能解释了两种治疗形式后病理活性降低的记录。然而，石英暴露后浸泡在Al-Lac溶液中的效果比吸入Al-lac更有效。天然石英和吸入的乳酸铝石英的半衰期分别为5.05个月和4.99个月，而经Al处理的石英半衰期为3.1个月。暴露第二个月后进行Al-lac吸入对沉积石英的清除率没有显著影响。
