Summary: | Cis-platinum is a widely used cytotoxic agent with known radiosensitising properties. It is used in the treatment of various types of lung cancer that may include radiation to the lung as part of the treatment protocol. There is little evidence and some conflict as to whether it sensitises pulmonary tissue to the effects of radiation treatment. This project investigates the effect of cis-platinum alone or in combination with radiation on mouse lung. Four end points were used to evaluate treatments. They were: the release of pulmonary surfactant, changes in breathing rate, a histology based score of damage and changes in TGF-β - a cytokine important in the development of fibrosis. Single doses of either cis-platinum or radiation, cis-platinum given immediately before a single dose of radiation, cis-platinum given immediately before the first of two fractions of radiation and cis-platinum given at various times before and after a single dose of radiation were investigated. Cis-platinum alone was observed to cause an increase in the phospholipid content of lavaged surfactant. Cis-platinum was observed to cause an early release in surfactant and a trend existed for it to induce an early increase in breathing rates as compared to that induced by radiation alone. Cis-platinum was observed to increase radiation damage as assessed using a histology based scoring system. Higher TGF-β levels in lavaged surfactant were observed in C57 /Bl mice as compared to Balb/C. No difference in TGF-β levels was seen in homogenised lung between the strains. Cis-platinum may cause changes in TGF-β in C57/Bl mice but further work is necessary to confirm this.
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