Effect of radiocontrast agents on intrarenal nitric oxide (NO) and NO synthase activity.

Background/aims: Contrast media (CM) induce a biphasic renal hemodynamic response, with late prominent cortical vasoconstriction and marked outer medullary vasodilation. The objective of the study was to explore a possible role for altered nitric oxide (NO) production or bioavailability in these hemodynamic responses.

Methods: We explored the impact of CM (sodium iothalamate) upon rat renal NO synthase (NOS) activity (citrulline recovery) and NO (using a NO electrode).