妊娠期尼古丁暴露对子鼠脏器发育的影响

Effect of nicotine exposure during maternal pregnancy on organ development of offspring mice

目的探讨妊娠期尼古丁暴露对小鼠子代脏器发育的影响。方法昆明孕小鼠24只,随机分为对照组和1、2、4 mg/kg尼古丁暴露组,各组小鼠自孕7 d至分娩,分别多点皮下注射1 m L生理盐水或尼古丁生理盐水溶液(尼古丁含量分别为1、2、4 mg/kg),1次/d。子鼠哺乳喂养,21 d断乳。检测子鼠出生3、7、14、21、35 d时的体重及子鼠5周龄时的脑、肝、心、脾、肾脏器系数及组织形态。结果各尼古丁暴露组子鼠初始出生时体重均低于对照组(P<0.05),出生35 d时,各组子鼠体重随尼古丁暴露剂量增高而降低(P<0.05);5周龄时,子鼠心肌纤维萎缩,心肌纤维间隙增大;肝细胞水肿;脾脏特征性结构边界不清,白髓面积变小,红髓面积增大等;大脑海马和肾组织未见明显异常。尼古丁暴露剂量达到2 mg/kg时,子鼠心脏和脾脏的脏器系数均显著上降(P<0.05)。结论妊娠期尼古丁暴露导致子鼠多器官组织形态异常,这可能是尼古丁致生后远期慢性疾病发生的解剖学基础和发育源性病因。

Objective To investigate the effects of nicotine exposure during pregnancy on organ development of offspring mice.Methods Twenty-four pregnant Kunming mice were randomly and evenly divided into four groups.Mother mice were subcutaneously injected with nicotine saline at 0, 1, 2, 4 mg/kg daily from gestation day 7 to childbirth.Body weight of offspring was monitored from birth to postnatal 35 days.Offspring brain, heart, liver, spleen, and kidney were observed under microscope.Results Compared with the control, the weights of offspring in nicotine exposure groups were all de-creased （P〈0.05）.At the postnatal day 35, the weights decreased with the increasing of nicotine concentration.The at-rophy in myocardial fibers, hydropic degeneration in liver cells, and obscure characteristic structure of spleen with atrophic white pulp and expanded red pulp were found under microscope.Conclusion Nicotine exposure during pregnancy could re-sult in abnormal morphology in multiple organs of offspring mice, which might be the anatomical basis and pathogeny of chronic diseases in later life.