Expression of disrupted-in-schizophrenia 1 in hippocampus in postpartum depression animal models induced by pre-pregnancy stress

Objective To establish a postpartum depression animal model induced by pre-pregnancy stress, assess abnormal maternal depressive-like behavior, observe the expression of disrupted -in-schizophrenia 1 (DISC1) in the hippocampus, and detect serum estradiol and corticosterone. Methods A total of 32 female Balb/c were assigned to two groups using random number table; the control group and the pre-pregnancy stressed group (model group) , and the model group was subjected to 3 weeks of chronic restraint stress. After the last stressor, the control group and the model group were housed with a male. About 4 weeks later, the mice gave birth to pups. Then at 3 weeks postpartum, open field test, tail suspension test, and sucrose preference test were carried out. The expressions of DISC1 mRNA and protein of hippocampus were detected by real-time quantitative polymerase chain reaction and Western blot, respectively. The serum levels of estradiol and corticosterone were detected with enzyme linked immunosorbent assay. Results After 3 weeks of postpartum, the model mice showed depression-like behaviors. In the open field test, there was no effect on the total distance moved or time spent in the center field ( P > 0. 05 ) . Immobility in tail suspension test was significantly increased ( t = - 4. 950, P < 0. 001) and sucrose preference was significantly reduced in model group ( t = 2. 475 , P < 0. 05). There was significant statistical difference between control and model group on the expression of DISC1 mRNA ( t = - 8. 915 , P< 0. 001) and protein( t = - 5. 004 , P< 0. 01) in hippocampus. There was no significant statistical difference on estradiol and corticosterone between two groups (P > 0. 05) . Conclusions Chronic prepregnancy stress can induce dams into postpartum depression. The pathogenesis of postpartum depression may be related to the regulation of DISC1 in the hippocampus.