Corticosterone microinjected into nucleus pontis oralis increases tonic immobility in rats

► We studied the effects of corticosterone in pons on some motor behaviors. ► Corticosterone intra-PnO increased the duration of tonic immobility in rats. ► Corticosterone intra-PnO increased the open-field motor activity of rats. ► The effects of corticosterone intra-PnO were blocked by MR or GR antagonists. ► Corticosterone released by stress can reach PnO to modulate tonic immobility.