Effect of transforming growth factor-β_1 in ventilator induced lung injury

Objective To investigate the role of transforming growth factor-β1(TGF-β1)in ventilator induced lung injury(VILI),and to explore VILI mechanisms.Methods Forty healthy male Wistar rats were randomly divided into the control group(without mechanical ventilation after intubation) and experimental group(after intubation mechanical ventilation:tidal volume 20 ml·kg-1,frequency of 50 times/min,respiratory absorption ratio of 1∶ 3,FiO2 21%,ventilation Time:5 h),changes in arterial partial pressure of oxygen observed before and after experiment.We took the central part of the lung tissue from left lung,produced lung tissue,and used streptavidin-biotin-peroxidase complex(SABC) method on lung bronchial epithelial cells,immunohistochemical staining of condncted TGF-β1 protein expression,used MIAS-2000 image analysis system for semi-quantitative analysis of proteins,and used the maximum gray value to show the amount of TGF-β1 protein expression.The remaining lung tissue was fixed with 4% paraformaldehyde solution,for 12 h,washed with PBS,embedded in paraffin to prepare paraffin tissue sections for pathological examination.Results There were no significant differences in arterial partial pressure of oxygen(P0.05).In the experimental group lung tissue TGF-β1 protein content was(15.66±1.30),while protein content of the control group was(3.10±0.95).TGF-β1 protein in the experimental group was significantly higher(P0.001),and lung edema can be seen in lung tissue biopsy.Conclusions Mechanical ventilation can cause lung injury.TGF-β1 may,in its genesis and development,plays an important role.