Effect of γ-aminobutyric acid preconditioning on pathological stretch-induced damage to type Ⅱ alveolar epithelial cells by mechanical ventilation / 临床麻醉学杂志

ABSTRACT

Objective To evaluate the effect of γ-aminobutyric acid (GABA) preconditioning on pathological stretch-induced damage to type Ⅱ alveolar epithelial cells by mechanical ventilation.Methods A549 cells cultured in vitro (0.2× 106/ml,2.5 ml/well) were randomly divided into 3 groups using a random number tablecontrol group (group C),pathological stretch group (group P) and GABA preconditioning+pathological stretch group (group G).A549 cells were exposed to 20％ cyclic stretch at 0.3 Hz for 6 h in groups P and G;GABA 50 μmol/L was given 30 min before cyclic stretch in group G.After the end of pathological stretch,the cells were collected for determination of the cell viability by methyl thiazolyl tetrazolium assay and lactate dehydrogenase (LDH) release by colorimetricmethod;the expression of F-actin was observed with indirect immunofluorescence;the expression of Rho-associated kinase 1 (ROCK1) and GABAAR were determined by western blot.Results Compared with group C,the cell viability was significantly decreased,the amount of LDH released was increased,the expression of ROCK1 was significantly increased and the expression of GABAAR was significantly decreased in groups P and G (P＜0.05);Compared with group P,the cell viability was significantly increased,the amount of LDH released was decreased,F-actin was re constructed,the expression of ROCK1 was significantly decreased and the expression of GABAAR was significantly increased (P＜0.05) in group G.The reconstruction of F-actin in group P was better than that in group G and worse than that in group C.Conclusion GABA preconditioning can attenuate pathological stretch-induced damage to type Ⅱ alveolar epithelial cells probably through up regulating the expression of GABAA receptor.