The effects of quetiapine on the improvement of behavior and expression of pERK1/2 in the hippocampus of chronic unpredictable stress model rats

Abstract

Objective To investigate the effect of quetiapine on the behavior and expression of pERK1/2 in chronic unpredictable stress(CUS) model rats. Methods 32 adult male Sprague Dawley rats were randomly divided into four groups(n=8 for each group): control group, CUS group, CUS+ QUE(5 mg/kg, L)group and CUS+ QUE(10 mg/kg, M)group. The rats in control group were left undisturbed in their home cage for 28 days and the other groups were exposed to 28 consecutive days of CUS, then the rats in control group and CUS group were treated with 1% DMSO in saline(5 ml/kg, intraperitoneal injection), the rats in CUS+ QUE(L)group and CUS+ QUE(M)group respectively treated with quetiapine(5 mg/kg)or quetiapine(10 mg/kg) for consecutive 7 days.The weight data of each group were recorded, and the behavioral changes in these rats were analyzed by open field test and forced swimming test; and the expression of pERK1/2 was measured by Western blot. Results (1) Compared with control group, quetiapine (10 mg/kg) ameliorated the inhibition of body weight gain that induced by chronic unpredictable stress (P 0.05). (3)The expression of pERK1/2 in CUS group showed significant decrease when compared with control group or CUS+ QUE(M)group, but showed no significant difference with CUS+ QUE(L)group(F=6.641, P<0.01). Conclusion Quetiapine can ameliorate depressive-like behaviors induced by chronic unpredictable stress, and this effect may be carried out by up-regulation the expression of pERK1/2 in the hippocampus. Key words: Qutiapine; Chronic unpredictable stress; Phosphorylated extracellular signal-regulated protein kinase; Rat; Hippocampus