Rapid antidepressant effect of Yueju ethanol extract on postpartum depression model mice induced by pre-pregnancy stress

To establish a postpartum depression animal model, assess the abnormal maternal behavior of depressive dams induced by pre-pregnancy stress; to observe the rapid antidepressant effects of the single Yueju (YJ, a traditional Chinese medicine) ethanol extract, acute ketamine (Ket) and chronic fluoxetine (Flx, served as control). Methods: Forty female BALB/c mice were randomly assigned to two groups, the control group and the pre-pregnancy stressed model group for 3 weeks' chronic restraint stress. After the last stressor, the model group was housed with a male. Then at the end of 3 weeks postpartum, we tested the maternal depressive-like behavior, including sucrose preference test (SPT), forced swimming test (FST), tail suspension test (TST), and novelty suppressed feeding test (NSF). Both YJ and Ket were single administered 24 hours before behavior test. While Flx was administrated once daily intraperitoneally (i. p) for 21 days, starting on postpartum day 1.Results: After 3 weeks postpartum, Mod showed depressive behaviors. Reduced preference in drinking sucrose solution were found in SPT (P<0.01). Immobility in FST and TST were significantly increased (P<0.01, P<0.01). In NSF, Mod displayed a significantly increase in latency and reduction in food consumption, compared with controls (P<0.01, P<0.01). Acute YJ improved performance in SPT(P<0.01), FST (P<0.01), and NSF (P<0.01, P<0.01), which was similar to Ket. While chronic Flx treatment, which was a SSRIS, could not change depressive behaviors of PPD mice. Conclusion: Chronic Flx did not improve depressive performance on PPD model induced by pre-pregnancy stress, indicating it's a refractory-like depression model. Acute YJ exerted fast antidepressant effect on the PPD model similar to Ket.