The Expression Of Type Ⅰ Procollagen And Transforming Growth Factorβ1 In Rat Early Acute Lung Injury Caused By Lipopolysacharide

ObjectiveTo observe the fibroproliferation occurs early in the acute lung injury (ALI) coused by lipopolysacharide ( LPS);to investigate the relationship between transforming growth factor - β1 ( TGF - β1) and early fibroproliferation of ALI.Methods27 SD rats were divided into 3 groups randomly, the NS group was instilled saline into trachea for 12h;and the lung sample were made . The LPS 1 group and LPS2 group were instilled LPS 1. 0 ml/kg (100μ g/ml)for 12h and 24h respectively ,and the lung sample were made. Type I procollagen peptide(PICP) was detected by ELISA in serum and bronchoalveolar lavage fluid ( BALF). TGF - (31 expression in lung was detected by immuohistochemistry. And find the relationship between them by liear correlation. Detected Wet/Dry weight of lung tissue.ResultsInstil LPS into trachea caused ALI in rats. The LPS2 group serum PICP concentration is 64.752 ±11. 966,was significantly higher than NS group(12. 380 ±3. 590) and LPS1 group (13. 959 ± 4. 304) ( P < 0. 05 ). NS group and LPS1 group are no significant difference (P > 0. 05 ). LPS2 group BALF PICP concentration is 35. 256 ±3. 324,was significantly higher than NS group(6. 899 ± 1.986) and LPS1 group(6. 0920 ±2. 502) (P <0. 05). NS group and LPS1group are no significant difference( P >0.05). Lung tissue TGF - pi expression in LPS2 group(140.081 ±21. 854) is significantly higher than LPS1(45. 157 ± 29. 443 ) ( P <0.05 ). The TGF - pi expression in the two injured groups( LPS1, LPS2 ) are significantly higher than NS group (7.175 ± 3. 686 ) (P < 0. 05 ). the concentration of PICP in serum and BALF after 24h positively correlate with the TGF - pi in lung tissue( correlation coefficient 0. 838,0. 801;degree of fredom n '=7,P<0. 05). The pulmonary section were stained with HE revealed the in-teralveolar markedly thicken, interstitial profiferation, and immersed by lymphocytes , macrophage, fibroblast . And such revealment are more significant after 24h than after 12h. The wet/dry weight of lung tissue indicate that the W/D of the two injured groups are significant higher than NS group (P <0. 05) after 12h, and it is no significant difference after 24h( P > 0. 05 ).ConclusionsThe significant increase of PICP in serum and BALF after 24h in LPS caused ALI indicate the existence of lung fibroproliferation. The positive correlation in concentration between TGF - pi and PICP of serum and BALF indicate that the TGF - pi improve the early lung fibroproliferation.