产前应用地塞米松对子代大鼠肺形态的影响

The Impact of Antenatal Dexamethasone Administration on the Lung Morphology of Rat Offspring

目的探讨产前应用地塞米松促肺成熟同时对子代大鼠肺形态是否有损害。方法15只SD大鼠孕鼠随机分成5组,孕后期处理组腹腔内注射不同剂量及疗程的地塞米松,对照组腹腔内注射等量生理盐水,生后1,8,21 d每组随机抽取8只幼鼠肺组织。肺组织切片HE染色,用图像分析测量以下指标:①肺泡间隔厚度;②肺泡面积:反映肺泡大小;③肺泡数。结果地塞米松组肺泡较对照组明显增大,肺泡间隔变薄,肺泡数减少。上述变化以大剂量多程组明显,一直持续到生后21 d差别仍存在。小剂量单程组则无明显差异。结论孕后期用地塞米松促肺成熟如增加疗程或剂量可能产生不良影响。

Objective To investigate effects of dexamethasone （Dex） administered to pregnant SD rats at late gestation on fetal lung morphology. Methods 15 gravid rats were randomly assigned to one of the 5 groups. At late gestation, for treatment group each was injected with various dosage and course of Dex, for control one each was injected with equivalent volumes of isotonic saline. Detections of rat offspring lung were done at day 1 ,day 8 and day 21 after birth. Samples of lung were HE stained. The following variables were calculated by digital image analysis. （ 1 ） Thickness of septal wall of alveoli. （2） surface area of alveoli. （3） number of alveoli. Results Significantly larger alveoli, thinner septal wall and fewer alveoli were observed in Dex - treated groups. These changes were evident in high dose repetitive course groups. The changes were found even at day 21. The low dose single course group had no significant change. Conclusions Antenatal dexamethasone administration at late gestation impaired alveolarization. When high dosage or repetitive courses of dexamethasone were administered for accelerating lung maturation at late gestation, side effects might accompany.