Effects of maternal rats exposed to chronic unpredictable stress before pregnancy on the postpartum behavior and neurobiology of themselves and their progency / 中华行为医学与脑科学杂志

ABSTRACT

Objective To determine the effects of maternal rats exposed to chronic unpredictable stress before pregnancy on the behavior and neurobiology of the mother and their offspring.Methods Two-month Virgin female Sprague-Dawley(SD) rats were applied to study.Females were housed with sexually experienced males (ratio 31) for propagation after 21-day chronic unpredictable stress.The behaviors of rats and their two-month-offspring were tested.The two-month rats were injected intraperitoneally with BrdU,then the brains were removed and 20 μm frozen sections were used to detect the neurogenesis of hippocampus.Results 1.Open field testafter lactation,CUS + Pre group ((720.52 ± 238.99) cm),CUS group ((995.62 ± 191.77) cm),CON group ((464.95 ±210.11)cm) and CON + Pre group((740.76 ± 281.48)cm) had statistic difference in total distance(P ＜ 0.05).The total distance((1281.10 ±247.89)cm) and border distance((1153.20 ±238.19)cm) in female two-monthprogeny were higher than these in male two-month-progeny ((1074.70 ± 263.35) cm,(957.28 ± 82.94) cm) in CUS + Pre group (P ＜ 0.05).2.Sucrose consumption testafter lactation,the sucrose intake ((13.00 ± 3.46) g)and sucrose consumption percentage((87.00 ±9.01)％) in CUS + Pre group were higher than that in CUS group ((8.13 ± 3.36) g,(79.06 ± 6.45) ％,P ＜ 0.05).The sucrose intake ((12.43 ± 3.31) g) and sucrose consumption percentage((86.90 ± 5.80)％) in CON group were higher than that in CUS group ((8.13 ± 3.36) g,(79.06 ± 6.45) ％,P ＜ 0.05).The sucrose intake ((14.71 ± 4.39) g) and sucrose consumption percentage ((91.54 ± 1.89) ％) in CON + Pre group were significantly higher than those in CUS group ((8.13 ± 3.36) g,(79.06 ± 6.45) ％) (P ＜ 0.01).3.Immunohistochemistrythere was no statistic difference on the new neuron in dentate gyrus of hippocampus in both female and male two-month-progeny of CUS group and CON group((1.18 ±0.37) cells,(1.24 ± 0.41) cells,(1.38 ± 0.47) cells,(1.41 ± 0.35) cells) (P ＞ 0.05).Conclusion The 21d CUS before pregnancy induce the anxiety-like behavior and depressive-like behavior in maternal rats,and lactation can attenuate influence of stress to protect maternal rats.There is no effect on the behavior and cell proliferation of hippocampus in adult progeny by chronic unpredictable stress exposure before pregnancy.However,there is the difference of anxiety-like behavior in both female and male two-month-progeny.