The effect of ACTH on the arterial blood pressure, heart rate and blood histamine level in rabbits.

A rapid blood pressure fall, persisting for over one hour, was observed after ACTH injection. The heart rate was initially increased and returned to its basal level within one hour. On the other hand, the level of histamine was significantly increased only in the 60th minute of the experiment. The results obtained showed that a possibility of an indirect ACTH action through an effect of histamine metabolism cannot be excluded.