Stress controllability and plasma prolactin levels in the rat

The effects of stress controllability on plasma prolactin levels were investigated in the rat. Animals were exposed to 60 trials of either escapable shock, inescapable shock or no shock. Rats in the escapable shock group exhibited higher levels of prolactin when compared to animals that could not control shock as well as no-shock controls. The results point to the involvement of coping factors in prolactin level changes induced by stress stimuli