机械通气对大鼠肺组织TGF-β/Smad信号通路相关蛋白的影响

Effects of mechanical ventilation on signal pathway TGF-β/ Smad in rats lung tissue

目的探讨机械通气对大鼠肺组织转化生长因子β(TGF-β)/Smad信号通路相关蛋白的影响。方法30只健康大鼠随机分为3组,每组10只。对照组插管后不进行机械通气,另两组进行机械通气,小潮气量组(L-VT)VT8 ml/kg,大潮气量组(H-VT)VT25 ml/kg,通气24 h。观察各组大鼠实验后肺病理变化,实验前(T1)、实验后6 h(T2)、实验后12 h(T3)、实验后24 h(T4)大鼠动脉血氧分压(Pa O2)变化及肺组织相关蛋白(TGF-β1、Smad2、Smad3、Smad7)水平变化。结果对照组及小潮气量组的肺组织未见明显的充血及水肿,大潮气量组可见肺间质水肿,肺内炎性细胞浸润。L-VT组各时间点Pa O2与对照组无显著差异(P>0.05);而H-VT组Pa O2在12 h后出现下降趋势(P<0.05)。随着机械通气潮气量的增加,TGF-β1、Smad2、Smad3表达呈现上调趋势,Smad7表达呈下降趋势。结论TGF-β/Smad信号通路相关蛋白可能作为呼吸机相关性肺损伤发病的重要参考指标。

Objective To investigate the effects of mechanical ventilation on signal pathway TGF-β /Smad in rats lung tissue. Methods30 rats into three groups were divided randomly with 10 cases per group. Control group received cannulation without mechanical ventilation,The other two groups received mechanical ventilation. L-VTgroup VT8 ml / kg,H-VTgroup VT 25 ml / kg with 24 h ventilation. To observe the pathology change of lung,Pa O2 change before（ T1） and 6h（ T2）,12 h（ T3）,24 h（ T4） after test and related protein（ TGF-β1、Smad2、Smad3、Smad7） change in per subgroup. Results The hyperemia and edema were not found in control group and L-VTgroup. The interstitial edema and inflammatory cell infiltration were found in H-VTgroup. There were not statistically significant of Pa O2 in L-VTgroup and control group at per time points（ P 0. 05）. Pa O2 in H-VT group reduced at 12 h after test（ P 0. 05）. TGF-β1,Smad2,Smad3 improved and Smad7 reduced by improving of tidal volume in mechanical ventilation. Conclusion Related protein of signal pathway TGF-β / Smad can be the important target of VALI.