Radiocontrast‐induced natriuresis associated with increased urinary urodilatin excretion

Abstract

Abstract. Haller C, Meyer M, Scheele T, Koch A, Forssmann W-G and Kübler W (University of Heidelberg; and Lower Saxony Institute for Peptide Research, Hanover; Germany). Radiocontrastinduced natriuresis associated with increased urinary urodilatin excretion (original article). J Intern Med 1998; 243: 155-62.Objective. Intravascular radiocontrast agents induce a pronounced diuresis. The aim of the present study was to investigate the (patho-)physiological mechanisms of the radiocontrast-induced diuresis. Design. The fractional excretion of sodium, the urinary excretion of the renal natriuretic peptide urodilatin and the plasma concentration of atrial natriuretic peptide were measured in 42 unselected patients immediately before and after intravascular radiocontrast administration during coronary angiography. Setting. Cardiac catheterization laboratory of a university hospital. Results. After angiography both the plasma concentration of atrial natriuretic peptide (median post-pre difference: 3.9 pmol L Ϫ1 , quartiles Ϫ1.2; 7.0) and the urinary excretion of urodilatin (median post-pre difference: 67.0 nmol urodilatin/mol creatinine, quartiles 39.7; 152.1) were increased. The urinary urodilatin excretion was correlated with an increase in the fractional excretion of sodium (median post-pre difference: 1.7%, quartiles 0.6; 3.1). There was no correlation between the serum concentration of atrial natriuretic peptide and urinary sodium excretion. For the radiocontrast-induced increase in both urodilatin and sodium excretion there was no indication for differences between patients without (31) and with (11) intravenous saline infusion. Conclusion. The radiocontrast-induced diuresis is a natriuresis which is associated with an increased urinary excretion of urodilatin. The association between natriuresis and urinary urodilatin excretion irrespective of baseline volume status corroborates the hypothesis that urodilatin contributes to the sodium excretion after radiocontrast administration in a paracrine manner. This finding has pathophysiological and potentially therapeutic implications in radiocontrast-induced nephropathy.

Efeitos cardiovasculares e renais da injeção intra-arterial de contraste radiológico iônico em cães com restrição hídrica

“…The two latter could be explained by osmotic diuresis-induced dilution. Some studies, in agreement with ours, have shown increased UE Na+ 12,31,32 and FE Na+ 32 after ionic and non-ionic radiological contrast, which seems to be independent of contrast osmolality. Increased sodium excretion cannot be explained by sodium content in radiological contrast: diatrizoate has high sodium concentration, while ioxilan, iopamidol, iohexol and other low osmolality contrasts have very low concentrations of this electrolyte.…”

Intravascular Radiocontrast Iodixanol Increases Permeability of Proximal Tubule Epithelium

“…8,9 We are curious whether Iodixnaol has high direct toxicity on kidney tubular cells, thus contributing to CIN. Moreover, the fact that radiocontrast agents could induce pronounced natriuresis 10 indicates that a contrast agent may cause kidney tubule cell permeability change. In the present study, we investigated whether Iodixanol causes a direct toxicity on cultured renal tubular cells or causes kidney tubular cell junction permeability changes.…”

Effect of Radiocontrasts on Selected Membrane Transport Systems

“…Contrast agents are almost exclusively removed by glomerular filtration, reaching the renal tubules at greatly increased concentrations. [32] Therefore, it is possible that the changes in L-arginine and choline transport, evidenced at high radiocontrast concentrations, are relevant to what occurs in kidney tubules on clinical exposure.…”