The effect of the right hemithoracic irradiation on the penetration of CAZ into the alveolar space in rats

The effect of irradiation on the transfer of antibiotic to the pulmonary tissue was examined in the period after irradiation using a unilateral lung irradiation model in rats. The results showed the following: 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 BALF, i.e., the permeability of the alveolar epithelium were found to reach the maximum 4-5 weeks after irradiation. 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 antibiotics 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 mechanism or some intracellular transport system caused by, for example, changes occurring at the alveolar level shortly after irradiation. (author)