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Updated: Jul 28, 2026
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5/6th Nephrectomy in Combination with High Salt Diet and Nitric Oxide Synthase Inhibition to Induce Chronic Kidney Disease in the Lewis Rat
Published on: July 3, 2013
Oxygen free radicals and contrast nephropathy
R E Katholi1, W T Woods, G J Taylor
1Prairie Education Research Cooperative, Springfield, IL, USA. REKatholi@aol.com
Summary
Ionic contrast media can harm kidneys. This study found that magnesium may protect against this kidney damage by reducing oxygen free radical injury in patients with mild renal dysfunction.
Area of Science:
- Nephrology
- Pharmacology
- Biochemistry
Background:
- Ionic, high-osmolality contrast media induce nephrotoxicity linked to increased intrarenal adenosine.
- Adenosine catabolism generates oxygen free radicals, potentially contributing to contrast-induced nephrotoxicity.
Purpose of the Study:
- To investigate the role of oxygen free radicals in contrast medium nephrotoxicity.
- To determine if magnesium protects against contrast-induced kidney injury mediated by oxygen free radicals.
Main Methods:
- 39 patients with mild renal dysfunction were randomized to low or normal magnesium states.
- Patients received either allopurinol (xanthine oxidase inhibitor) or placebo before coronary angiography.
- Creatinine clearance and urinary xanthine excretion were measured pre- and post-angiography.
Main Results:
- Placebo groups showed increased urinary xanthine excretion post-contrast.
- Hypomagnesemic patients (LoMg++) experienced a significantly greater decrease in creatinine clearance compared to normal magnesium patients (NlMg++).
- Allopurinol administration prevented xanthine increase and attenuated creatinine clearance reduction in both magnesium groups.
Conclusions:
- Oxygen free radicals contribute to contrast medium nephrotoxicity in hypomagnesemic patients with mild renal disease.
- Magnesium attenuates contrast-induced nephrotoxicity, likely by mitigating oxygen free radical-mediated kidney injury.
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