母鼠不同孕期巨细胞病毒感染对仔鼠发育及行为的影响

Effects of maternal cytomegalovirus infection in different trimesters of pregnancy on the growth and behavior of offspring mice

目的研究母代不同孕期巨细胞病毒(CMV)感染对子代发育及行为的影响。方法研究于2017—2020年期间选取BALB/c雌鼠36只,随机分成12组(A1、A2、A3、B1、B2、B3、C1、C2、C3、D1、D2、D3,每组3只),A为孕期再感染组,B为既往感染组,C为孕期原发感染组、D为正常对照组,1为孕早期,2为孕中期,3为孕晚期。母鼠腹腔注射小鼠CMVSmith株建立播散性感染模型,或注射无菌生理盐水建立对照模型。母鼠产仔后同笼合养,产后22天分笼,每组随机选6只仔鼠做行为学试验。试验结束后,每组随机处死3只仔鼠,测量脑脏器重量系数及唾液腺中MCMV含量。结果 A、C组仔鼠比D组仔鼠出生体重低(td值分别为2.42、3.34,P<0.05),脑脏器重量系数高(td值分别为2.69、4.17,P<0.05)。A、B、C组仔鼠唾液腺组织均测出MCMV。A1、C1组仔鼠脑组织病理表现异常。6周时,与D组仔鼠比较,C3组仔鼠的水平运动总距离缩短(F=23.44,P<0.05),直立次数减少(F=16.25,P<0.05),悬尾不动时间延长(F=14.03,P<0.05),糖水偏好指数降低(F=9.98,P<0.05);A1、C1组仔鼠的逃避潜伏期时间延长(F值分别为15.33、23.78,P<0.05),穿越原平台位置次数减少(F值分别为14.12、22.21,P<0.05)。结论母代孕期CMV感染影响子代身心健康成长,孕期原发感染危害更长远。

Objective To investigate the effects of maternal cytomegalovirus(CMV) infection in different trimesters of pregnancy on the growth and behavior of offspring.Methods 36 female BALB/c mice were selected from 2017 to 2020 and randomly divided into 12 groups,including A1,A2,A3,B1,B2,B3,C1,C2,C3,D1,D2,D3 group(A meant re-infection,B meant past infection,C meant primary infection,D meant blank control,while 1 meant the first trimester,2 meant the second trimester,3 meant the third trimester),with 3 mice in each group.The murine cytomegalovirus(MCMV) disseminative infection model was established by intraperitoneal inoculation of MCMV Smith strain,and the blank control model was established by intraperitoneal inoculation of 0.9% sterile normal saline.The maternal and offspring mice were reared together in the cage after birth,and thenreared in separate cages after 22 days of parturition.Six offspring mice from each group were randomly selected for behavioral test.At the end of tests,3 offspring in each group were killed randomly,and the organ weight coefficients of brainand the expression levels of MCMV in salivary gland weredetected.Results The birth weights of newborn rats in groups A and C were lower than those in group D(td=2.42 and 3.34,respectively,P<0.05).The organ weight coefficients of brain in groups A and C were higher than those in group D(td=2.69 and 4.17,respectively,P<0.05).The MCMV in salivary gland tissue werefound in groups A,B and C,but not in group D.The pathological features of brain tissues were abnormal in groups A1 and C1.Compared with group D,the offspring mice of group C3 had shorter total horizontal movement distance(F=23.44,P<0.05),less upright frequency(F=16.25,P<0.05),longer immobility time of tail suspension(F=14.03,P<0.05) and lower sugar preference index(F=9.98,P<0.05) at 6 weeks after birth.And compared with group D,the escape latency of offspring mice of in group A1 and C1 at 6 weeks after birth were prolonged(F=15.33 and 23.78,respectively,P<0.05),and the times of crossing the original platform were reduced(F=14.12 and 22.21,respectively,P<0.05).Conclusion Maternal CMV infection affects the physical and mental health of the offspring,and the primary infection during pregnancy is more harmful in the long term.