Objective: To observe the effect of methylprednisolone on procollagen type III of rats with acute lung injury (ALI) induced by endotoxin.
Methods: Forty-five rats were randomly divided into three groups: endotoxin group, endotoxin plus methylprednisolone group, and control group, with 15 rats in each group. The model of ALI in rat was reproduced by intravenous injection of endotoxin in the dose of 6 mg/kg. On 1, 3, 14 days after the onset of ALI in rats, total cell number, classification of polymorphonuclear neutrophil (PMN), macrophages and procollagen type III in serum and bronchoalveolar lavage fluid (BALF) were determined by radioimmunology.
Results: Total cell number, classification of PMN and macrophages in BALF as well as procollagen type III level in serum and BALF were obviously increased in endotoxin group on the first day, then decreased gradually (all P<0.01). Methylprednisolone inhibited the increase of the above-mentioned parameters (P<0.05 or P<0.01).
Conclusion: Methylprednisolone can inhibit the increase of the procollagen type III levels in serum and BALF in rats with acute lung injury induced by endotoxin.