ABSTRACT

Among the mechanisms of contrast media induced renal dysfunction, renal ischemic iniury is the main reason and some of the vasoactive substances may mediate the renal haemodynamic effects of contrast media(CM). The present study was designed to determine the role of nitric oxide and endothelin on occurrence of contrast media nephrotoxicity.

A total of 20 patients were given one of the following tow osmolar CM; iopamtdol, topromid or iohexol (or abdominal computed tomography scanning. Blood samples for endothelin and nitric oxide metabolites (NOx: nitrate, nitrite) were drawn iust prior to and 10 minutes after the contrast media administration. Serum creatinine levels were determined prior to the administration of contrast media and on the first and third postscanning days. Radioimmunoassay for endothelin was performed while NOx was measured byustng Sievers !nstruments Model 280 A Nitric Oxide Analyser.

Intravascular administration of CM appeared to elicit a rise in plasma endothelin but this was not statistically significant (p=0./54). Contrast media also did not affect the nitrate (p=O. 709) and nitrite(p=0.699) levels significantly. Mean serum creatinine levels increased significantly from 0.62±0.13mgldl to 0.72±0.22 mgldl (p=0.049). There was a weak correlation between baseline endothelin levels and the change in serum creatinine over the three days (r=0.39, p=0.088).

In this study, we have demonstrate« that CM did not interfere with serum NOx and endothelin levels. It is feasible to suggest that mtric oxide is unlike[} play a maior role in the haemodynamic effects induced b} CM. However the role of ET in the pathophysiology of contrast media nephrotoxicity cannot be eliminated in this study because of the study protocol which excluded the patients with predisposing factors.