Effect of high tidal volume mechanical ventilation on the expression of interleukin-1β in the pulmonary tissue of rat

Objective To examine the effect of high tidal volume mechanical ventilation on the expression of interleukin-1β(IL-1β) in the pulmonary tissue of rat.Methods 24 healthy sprague dawley(SD) rats were randomly divided into control group,conventional ventilation group(VT=8ml/kg) and ventilator associated lung injury group(VALI, VT=40ml/kg).Rats were sacrificed and the lung lavage liquid and lung tissue were collected and stored with correct methods. The contents of total protein,white blood cell(WBC),MPO and ratio of wet/dry lung tissue(W/D) were measured.The level of IL-1βprotein and IL-1βmRNA was dertermined by ELISA and RT-PCR respectively.Results The number of WBC and the value of MPO in bronchial alveolar lavage fluid(BALF),the ratio of W/D,the levels of total protein of IL-1βprotein and IL-1βmRNA in BALF significantly increased in VALI group(P0.05) compared with conventional ventilation group or control group.Conclusion High tidal volume ventilation induces the expression of IL-1βand causes lung injury.