Abstract: Objective To investigate the effects of overfeeding during lactation on organ development of offspring mice. Methods A total of 20 Kunming pregnant mice were randomly divided into two groups,control and study group,which were treated with same condition during pregnancy.After delivery,all mothers reared their pups freely.At postnatal day 3,the litters of each group were culled to keep litter size at 4 pups/litter in study group and 10～12 pups/litter in control group.After weaning,all pups were fed with standard lab diet.Physical development of offspring was monitored from birth to postnatal 6 weeks.Organ coefficients of offspring major organs were determined and the morphology of them was observed through HE staining under microscope at age of 6 weeks. Results 1)Physical developmentat age of 3 and 6 weeks,the bodyweight of pups of study group were significantly higher than those of control group (P<0.05).2)Organ coefficientthe organ coefficients of heart,liver and spleen were significantly higher in offspring of study group than those in control group (P<0.05).3)Morphologyunder microscope,compared with offspring of control group,atrial and ventricular walls of heart were thicker,liver cells presented slight edema,and boundary of white pulp,red pulp and marginal zone in spleen was obscure in offspring of study group. Conclusions Overfeeding during lactation results in obesity during childhood and young adulthood,as well as morphological changes of some organs in offspring.These morphological abnormities might be the anatomical basis of influence of overfeeding during lactation on later disease.The profound mechanisms are worthy of further study.

Key words: lactation, overfeeding, offspring, development, organ

摘要： 目的 探讨哺乳期过度喂养对子代小鼠器官发育影响,为深入研究哺乳期过度喂养对远期健康和疾病的影响提供科学依据。方法 20只昆明种孕鼠随机分为对照组和实验组,孕期条件相同,产后母乳喂养,产后3 d调整每窝子鼠数为实验组4只,对照组10～12只;3周断乳,其后两组子鼠均以标准饲料喂养。监测子鼠体格发育情况,生后6周测定子鼠心、肝、胰、脾、肾和脑脏器系数,并检测各器官组织形态。结果 1)体格发育:生后3周和6周,实验组子鼠体重显著大于对照组(P<0.05);2)脏器系数:生后6周,实验组子鼠心、肝、脾脏器系数显著高于对照组(P<0.05);3)组织形态:与对照组子鼠比较,实验组子鼠心脏房、室壁厚度增加,心肌纤维横截面积增大,心肌纤维厚度增宽;肝细胞呈轻度水肿表现;脾脏红、白髓以及边缘区结构不清,白髓发育不良。结论 哺乳期过度喂养可导致子代生后近、远期肥胖,对某些器官造成形态学影响,后者可能是生命早期过度喂养影响生后远期健康的解剖学基础,其机制值得深入研究。

关键词: 哺乳期, 过度喂养, 子代, 生长发育, 器官