Cardiovascular and Renal Responses to the Combination of Hexamethonium and 1-Hydrazinophthalazine (Apresoline®) in Hypertensive Subjects1

Abstract

Using standard techniques, renal and cardiovascular adjustments were measured in 18 hypertensive patients when 1-hydrazinophthalazine was given intravensouly alone, and preceeded by hexamethonium ions. It was shown that the rise in renal plasma flow following the 1-hydrazinophthalazine could not be blocked by prior administration of hexamethonium. Also, the rise in renal plasma flow was noted only in those patients with relatively normal control values. On the other hand, the rise in cardiac output almost invariably noted after 1-hydrazinophthalazine could be blocked almost completely by the prior administration of a small dose of hexamethonium. This offers some rationale for the combined use of these 2 drugs in therapy of severely hypertensive patients in order to circumvent the cardiostimulating properties of 1-hydrazinophthalazine. It would appear that the level of renal plasma flow after 1-hydra-zinophthalazine in these patients was independent of the cardiac output.