Comparative study of the adverse effects of various radiographic contrast media, including ioversol, a new low-osmolarity medium. II. The complement system and endothelial cells.

: The effects of ioversol, iohexol, iopamidol and meglumine sodium amidotrizoate (MSA) on the complement system and endothelial cells were investigated. The protein bindings of the radiographic contrast media (RCM), each tested with guinea pig plasma, were less than 1%. When guinea pig serum was incubated with any of the RCM, activation of the complement system, which leads to hemolysis, was not influenced by the nonionic agents, ioversol, iohexol or iopamidol. However, MSA, an ionic agent, significantly reduced hemolytic activity at 370 mgI/ml. Perfusion of the abdominal aorta with nonionic agents did not elicit significant endothelial damage; ioversol induced the least damage among the nonionic RCM, while MSA caused remarkable endothelial damage. Although MSA caused a marked release of endothelin-1 from cultured endothelial cells obtained from porcine aorta, nonionic RCM did not induce significant endothelin-1 release; no influence was elicited by ioversol and iohexol caused a weak suppression, while iopamidol had the opposite effect. These results indicate that ioversol could be used as a safe contrast medium in intravascular administration.