妊娠期应激致子代小鼠注意缺陷多动障碍样行为及机制研究

Maternal stress during pregnancy leads to ADHD like behavior in offspring mice and its mechanism

目的探讨妊娠期应激致子代小鼠注意缺陷多动障碍(attention deficit/hyperactivity disorder,ADHD)样行为及其机制。方法对不同孕期ICR孕鼠施行慢性不可预知性应激(chronic unpredictable mild stress,CUMS),随机选择其子代小鼠并观察各组(CG:对照组;SG1:孕8~14 d CUMS;SG2:孕15 d~分娩CUMS)在旷场实验中的行为及ELISA法检测各组血浆γ-氨基丁酸(γ-aminobutyric acid,GABA)及其代谢酶和多巴胺(dopamine,DA)浓度。结果旷场实验结果显示,SG1组、SG2组和CG组三组小鼠的运动总路程、中央区停留时间、中央区速度、周围区速度均差异有统计学意义(F=8.30,5.01,8.05,7.15;均P<0.05)。SG1组和SG2组小鼠活动的总路程明显长于CG组[(5221.07±469.95)mm,(4825.63±545.49)mm,(3781.17±1111.34)mm;均P<0.05];SG1组和SG2组小鼠在中央区停留时间比CG组短[(5.95±3.32)s,(8.59±3.42)s,(11.10±3.61)s;均P<0.05];SG1组和SG2组小鼠的中央区活动速度比CG组快[(30.93±5.79)mm/s,(32.48±9.06)mm/s,(20.57±5.07)mm/s;均P<0.05];SG1组小鼠周围区活动速度比CG组快[(16.91±1.64)mm/s,(12.42±3.77)mm/s;P<0.05]。ELISA结果显示,CG组、SG1组和SG2组三组小鼠的血浆GABA、GAD65、GAD67和DA均差异有统计学意义(F=16.52,6.42,11.04,7.26;均P<0.05)。SG1组和SG2组小鼠血浆GABA浓度低于CG组[(3.70±0.80)μmol/L,(4.40±0.80)μmol/L,(6.06±1.01)μmol/L;均P<0.05];SG1组小鼠的血浆GAD65浓度[(5.36±0.75)μg/L,(6.99±1.01)μg/L,P<0.05]和GAD67浓度[(10.52±1.09)μg/L,(9.84±1.35)μg/L,(12.83±1.67)μg/L,均P<0.05]低于CG组。SG1组小鼠血浆DA浓度[(82.81±8.59)ng/L]高于CG组[(69.43±9.42)ng/L,P<0.05]和SG2组[(66.36±10.77)ng/L,P<0.05]。结论妊娠期应激导致子代小鼠表现出ADHD样行为,可能与影响了血浆GABA代谢和DA浓度有关。

Objective To investigate the attention deficit/hyperactivity disorder(ADHD)like behavior of offspring mice induced by stress during pregnancy and its mechanism.Methods Chronic unpredictable stress was applied to ICR pregnant mice in different gestational periods.The offspring mice were randomly selected and the behavior changes of each group were observed in open field experiment(CG:control group;SG1:cums stress stimulation from 8 to 14 days of gestation;SG2:cums stress stimulation from 15 days of gestation to childbirth).The plasma concentrations of GABA,its metabolic enzymes and dopamine were detected by ELISA.Results The results of open field experiment showed that the total distance,the time of stay in central area,the speed in central area,and the speed in surrounding area in SG1 group,SG2 group and CG group were statistically significant(F=8.30,5.01,8.05,7.15,all P<0.05).The total distances of SG1 group and SG2 group were significantly longer than that of CG group((5221.07±469.95)mm,(4825.63±545.49)mm,(3781.17±111.34)mm,both P<0.05).The times of stay in central area of SG1 and SG2 groups were shorter than that in CG group((5.95±3.32)s,(8.59±3.42)s,(11.10±3.61)s,all P<0.05).The speeds in central area of SG1 and SG2 groups were faster than that of CG group((30.93±5.79)mm/s,(32.48±9.06)mm/s,(20.57±5.07)mm/s,all P<0.05).The speed in surrounding area in SG1 group was faster than that in CG group((16.91±1.64)mm/s),(12.42±3.77)mm/s,P<0.05).ELISA results showed that there were significant differences in mice plasma GABA,GAD65,GAD67 and DA among CG group,SG1 group and SG2 group(F=16.52,6.42,11.04,7.26,all P<0.05).The plasma concentrations of GABA in SG1 group and SG2 group were lower than that in CG group((3.70±0.80)μmol/L,(4.40±0.80)μmol/L,(6.06±1.01)μmol/L,all P<0.05).The plasma concentrations of GAD65((5.36±0.75)μg/L,(6.99±1.01)μg/L,P<0.05)and GAD67((10.52±1.09)μg/L,(9.84±1.35)μg/L,(12.83±1.67)μg/L,P<0.05)in SG1 group were lower than those in CG group.The plasma DA concentration in SG1 group((82.81±8.59)ng/L)was higher than that in CG group((69.43±9.42)ng/L,P<0.05)and SG2 group((66.36±10.77)ng/L,P<0.05).Conclusion Prenatal stress can induce ADHD-like behavioural phenotypes in offspring mice,which may be related to the influence of plasma GABA metabolism and DA concentration.