The effects of an inhibitor of phenylethanolamine N-methyltransferase upon stimulated adrenal catecholamine release and excretion in the rat.

SK&F 64139, an inhibitor of adrenal phenylethanolamine N-methyltransferase (PNMT), was found to significantly decrease 2-deoxy-D-glucose (2-DG) induced epinephrine excretion in the conscious rat under conditions where the former agent was administered chromically at 50 and 200 mg/kg/day over a 12-day period and 2-DG was administered after 3, 7 and 11 days of treatment. The reduced epinephrine output caused by SK&F 64139 in response to 2-DG was accompanied by an increased norepinephrine excretion pattern at 200 mg/kg/day of the compound. The reductions in epinephrine excretion were also associated with significant decreases in adrenal epinephrine and increases in the norepinephrine content.