Establishment of a chronic restraint stress model of depression with C57BL/6J mice.

To establish a chronic restraint stress (CRS) model of depression,using C57BL/6J mice.Totally 20 C57BL/6J mice were screened by weight,sucrose preference,and the results of open-field test. Then,they were equally randomized into two groups:normal control (NC) group and CRS group. Mice in the CRS group were under restraint 4 hours a day and their behavioral changes were evaluated after 21 days.The immobility time was significantly longer in CRS mice [(131.70 ± 21.65) s] compared with controls [(68.88 ± 8.43) s] (P=0.0304). CRS mice showed a significant decrease in sucrose preference during the time 0-24 h [(66.21 ±3.24)% vs.(79.46 ± 3.85)%, P=0.0196] and 0-48 h [(73.25 ± 1.50)% vs.(80.20 ± 2.26)%, P=0.0248] compared with controls.The C57BL/6J mice CRS models of depression were successfully established.