INHIBITION OF COLLAGEN ACCUMULATION BY GLUCOCORTICOIDS IN RAT LUNG AFTER INTRA-TRACHEAL BLEOMYCIN INSTILLATION

  • 1 January 1982
    • journal article
    • research article
    • Vol. 42  (2) , 405-408
Abstract
Male Fischer 344 rats were given a single lung instillation of bleomycin sulfate (0.6 U/100 g) [an antitumor antibiotic which has side effects of interstitial pneumonia followed by fibrosis]. Some animals were treated 24 h after bleomycin administration with triamcinolone diacetate. Steroid treatment was continued on alternate days for 4 wk. At the end of 4 wk, the lungs of rats receiving bleomycin alone had 2-fold increases of both prolyl hydroxylase activity and proteinaceous hydroxyproline as compared to control values. The lungs of bleomycin-treated rats which received 4 mg of triamcinolone diacetate/kg on alternate days had a 33% increase of prolyl hydroxylase activity and a 37% increase of proteinaceous hydroxyproline content as compared to control values. Lung prolyl hydroxylase activity and proteinaceous hydroxyproline content of bleomycin-treated animals receiving glucocorticoid (8 mg/kg) on alternate days were the same as control values. Apparently, alternate day administration of the synthetic glucocorticoid triamcinolone diacetate blocks lung collagen accumulation of following a single intratracheal dose of bleomycin to rats.