薬剤の肺組織移行に胸部放射線照射が及ぼす影響について

The Effect of the Right Ilemithoracic Irradiation on the Penetration of CAZ into the Alveolar Space in Rats

　胸部放射線照射に伴う肺の急性期障害を経時的に捉えることを目的として，抗生物質の肺組織移行を指標として，ラットの片側肺照射モデルを用いて検討した．その結果，以下のことが示された．1） CAZの肺毛細血管上皮の透過性は照射2週間後より漸増し，照射4週間後でピークとなった．2） CAZの肺胞上皮の透過性は照射直後から上昇し，照射1週間後と5週間後の2相性のピークを呈し，後者が前者を上回った．3）肺組織内CAZ絶対量の経時的変化において，非照射側肺においても照射側同様，照射3日後より対照群と比べて有意な上昇を認めた．以上の結果より，胸部放射線照射中の急性肺障害の早期発見には照射直後からの，照射野外も含めた詳細な理学的所見の採取，経過観察などが肝要であると思われた．

The effect of irradiation on the transfer of antibioticto the pulmonary tissue was examined in the period after irradiation using a unilateral lung irradiation model in rats. The results showed the following: 1) Both transfer of CAZ from blood to the lung tissue, i.e., the permeability of pulmonary capillary epithelium, and transfer of CAZ from the lung tissue to BALE, i.e., the permeability of the alveolar epithelium were found to reach the maximum 4~5 weeks after irradiation. 2) In the time-course changes of the absolute amount of CAZ in the lung tissue, the amount in the control lung as well as that in the irradiated lung increased significantly from 3 days after irradiation onward when compared with control animals. Regarding the transfer of antibi-otics to the lung tissue, the changes in the lung of the non-irradiated side as well as that in the irradiated side were observed. These results suggest that the effect of irradiation may have been transmitted to the non-irradiated region by means of an immunological mecha-nism or some intracellular transport system caused by,for example, changes occurring at the alveolar level shortly after irradiation.