Antidepressant-like effects of paeoniflorin on the behavioural, biochemical, and neurochemical patterns of rats exposed to chronic unpredictable stress

► Chronic unpredictable stressors elicited evident alterations of behaviours in rats. ► Chronic paeoniflorin treatment had an antidepressant-like effect in CUS rats. ► Paeoniflorin decreased serum corticosterone and ACTH levels in CUS rats. ► Paeoniflorin modulated serotonergic and noradrenergic systems in CUS rats.