Histamine release and contrast media-induced renal vasoconstriction.

RATIONALE AND OBJECTIVES

The authors' purpose was to investigate the role of histamine release causing renal vasoconstriction induced by application of contrast media, an important element in contrast medium-induced nephrotoxicity.

MATERIALS AND METHODS

Isometric contractions in rabbit segmental renal arteries stimulated with KCl and increasing concentrations of the ionic contrast medium diatrizoate and the nonionic agents iomeprol and iodixanol were studied both with and without increasing concentrations of the histamine H1 and H2 blockers diphenhydramine and cimetidine. Histamine concentrations after contrast medium application were determined.

RESULTS

Contrast-induced, dose-dependent, reversible renal artery contractions of 27%, 4.5%, and 5% of the control KCl contraction were found for diatrizoate, iodixanol, and iomeprol respectively. Those induced by the ionic contrast medium were statistically significantly higher (P < .01). Contractions were partially inhibited by diphenhydramine (49%) but not by cimetidine. Significant elevation of histamine concentrations (P < .05) was detected only after stimulation with diatrizoate but not with nonionic agents.

CONCLUSION

Ionic contrast medium induces histamine release leading to renal vasoconstriction, which can be partly blocked by H1 blockers. Histamine has no effect on renal vasospasm induced by nonionic contrast media.