The influence of proline analogs on bleomycin-induced lung injury in rats.

The influence of 3,4-dehydro-DL-proline and 3,4-dehydro-L-proline on lysyl oxidase, prolyl hydroxylase activities, collagen cross-linking and types of collagen in bleomycin-induced lung injury was investigated. Both proline analogs cause a great fall in prolyl hydroxylase activity without effect on lysyl oxidase, diminish the number of cross-links and normalize the type I/type III collagen ratio. It is suggested that proline analogs may be valuable agents in lung fibrosis treatment.