Brain biogenic amines and pituitary-adrenocortical function in the rat.

Treatment of rats with various doses of the monoamine oxidase inhibitor (MAOI) pargyline failed to alter plasma levels of corticosterone at 18 hours post-dosage even though brain levels of serotonin and norepinephrine were increased by 51 to 95 percent. Single pargyline doses of 17.5 or 25 mg/kg blocked the increased plasma corticosterone response to reserpine. Animals pretreated with two doses of the MAOI showed a time-dependent sedative response to reserpine. In these animals, the plasma corticosterone response to reserpine was blocked, while the responses to cold exposure or chlorpromazine were unaffected.