产前用地塞米松对鼠肺泡形态发育的影响

The effect of antenatal administration of dexamethason (DXM) on the morphogenesis of alveoli in newborn rats

目的探讨孕期肌注地塞米松对新生大鼠肺泡形态发育的影响。方法16只SD孕大鼠分为对照组和观察组,每组8只,分别于孕18、19、20d肌注9gL氯化钠溶液0.5ml和地塞米松0.8mg·kg-1·d-1,以9gL氯化钠溶液稀释至0.5ml,足月自然分娩后取新生4、10、14日龄大鼠肺组织,病理切片,HE染色,观察肺泡形态学的改变,进行计算机图像分析。结果同日龄新生大鼠比较,观察组肺泡间隔厚度、肺泡表面积肺泡体积、肺泡数、次级隔高、次级隔数均低于对照组(均P<0.01),肺泡面积大于对照组(P<0.01。结论孕期肌注地塞米松可影响新生鼠肺泡形态发育,使呼吸膜面积减小,阻碍肺泡化。

Objective To investigate the effect of antenatal administration of dexamethason (DXM) on the morphogenesis of alveoli in newborn rats. Methods Sixteen Sprague-Dawley (SD) pregnant rats were divided into DXM group and control group with eight rats each on gestational day18, 19, 20, the animals were injected i.m with DXM (0.8mg·kg-1·day-1) or isotonic saline (0.5ml) respectively. After term delievered naturally, the lungs of newborn rats at age of 4, 10, 14d were examined. The tissue sections were stained with HE for light microscopic morphometric examination, and analyzed by a digital image analysis system. Results Compared with the control group, the thickness of interalveolar walls, alveolar surface area/alveolar volume (s/v), alveolar number, the number and length of secondary septa in the DXM group were decreased, while alveolar area was increased. Conclusion Antenatal DXM administration can affect the lung morphogenesis of newborn rats, which may impair the alveoli formation and decrease the gas exchange area.