Studies on myocardial histamine. Effects of catecholamine-depleting drugs.

Hearts of rats, mice and guinea-pigs were assayed in parallel for histamine and norepinephrine. Reserpine decreased the histamine content in the hearts of rats and mice but not in guinea-pigs. alpha-Methyltyrosine decreased the histamine content in both rat and guinea-pig hearts. 6-Hydroxydopamine increased myocardial histamine content in the rat but not in the mouse.