Effects of contrast media on aortic endothelium. Experiments in the rat with non-ionic monomeric and monoacidic dimeric contrast media.

Injury to the aortic endothelium in rats was evaluated under a light microscope by a silver staining method after application of ionic monomeric (diatrizoate and metrizoate), non-ionic monomeric (C29 with different pH and buffers, 593, iohexol and metrizamide) and monoacidic dimeric (ioxaglate) contrast media, and iso- and hypertonic solutions of sodium chloride. In iodine equivalent concentrations the ionic monomers were significantly more toxic than the other contrast media. No significant was found between the non-ionic monomers, monoacidic dimer and sodium chloride solutions equiosmolal to the ionic monomers. Isotonic saline was the least harmful solution.