Protective effects of cannabidiol against acute stress: behavioral responses and corticosterone concentrations in female Wistar rats.

BACKGROUND

Cannabidiol (CBD) has been widely investigated for its potential anxiolytic and stress-modulating effects. This study evaluated whether CBD reduces the stress response induced by acute restraint stress in rats.

METHODS

Thirty-six female Wistar rats were randomly assigned to six groups. Four experimental groups received CBD at different doses (2, 10, 20, and 100 mg/kg), while two control groups received the placebo (CBD vehicle medium-chain triglycerides). Sixty minutes after administration, the animals treated with CBD and one placebo-treated group (stressed control group) were subjected to 60 min of restraint stress. The other placebo-treated group (nonstressed control group) was not subjected to restraint stress. Subsequently, all animals were tested in the open field (OF) for 30 min. Immediately after the OF test, blood samples were collected for corticosterone analysis. Plasma corticosterone concentrations were determined using a commercial ELISA kit.

RESULTS

In the OF, distance traveled differed significantly between groups, although no significant differences were observed among the different CBD doses. Compared with stressed control rats, CBD-treated rats spent more time in the center of the OF arena, suggesting reduced anxiety-like behavior. Plasma corticosterone concentrations did not differ significantly between groups. At 90 min after the onset of stress (30 min after the end of restraint stress), corticosterone concentrations did not differ between CBD-treated and untreated rats.

CONCLUSION

CBD showed no effect on locomotor activity but increased center time, suggesting anxiolytic-like effects. Further studies are needed to clarify the underlying mechanisms.