Platelet and Fibrin Modification by Radiographic Contrast Media

• Published in: Circulation research Vol. 68; no. 3; pp. 881 - 887
• Main Authors: Gabriel, Don A, Jones, Marsha R, Reece, Neil S, Boothroyd, Emily, Bashore, Thomas
• Format: Journal Article
• Language: English
• Published: Hagerstown, MD American Heart Association, Inc 01.03.1991; Lippincott
• Subjects: Biological and medical sciences; Blood coagulation. Blood cells; Blood Platelets - drug effects; Contrast Media - pharmacology; Diatrizoate - pharmacology; Electrophoresis; Fibrin - chemistry; Fibrin - metabolism; Fundamental and applied biological sciences. Psychology; General aspects, investigation methods, hemostasis, fibrinolysis; Humans; Iopamidol - pharmacology; Light; Molecular and cellular biology; Scattering, Radiation; Aggregation; Radiography; Fibrin; Platelet; Fibrinogen; Coagulation factor; Contrast media
• ISSN: 0009-7330; 1524-4571
• DOI: 10.1161/01.RES.68.3.881

The effect of the radiographic contrast agents, iopamidol and diatrizoate, on fibrin assembly and structure as well as platelet surface charge was studied. Increasing the iopamidol concentration from 0 to 4.5 mM prolongs the fibrin gelation time from 20 to 105 seconds (an anticoagulant effect) and reduces the fibrin fiber mass/length ratio from 3.2×10 to 0.5×10 Da/cm (i.e., produces very thin fibrin fibers). Ultraviolet difference spectroscopy of fibrinogen showed both a 15-nm shift in the ultraviolet difference maximum for iopamidol (suggesting binding) and a perturbation of the aromatic amino acid side chain region for fibrinogen (suggesting a conformational change in fibrinogen) as the concentration of iopamidol was increased from 0 to 9 mg/ml. Binding of iopamidol to fibrinogen was also shown by affinity chromatography using a Sepharose-fibrinogen column. Electrophoretic quasi elastic light scattering was used to show platelet interaction with iopamidol as reflected in a reduction in the platelet electrophoretic mobility from 2.0 to 0.5 (μm-cm)/(V-sec) as the concentration of iopamidol was increased from 0 to 4.5 mM. In addition, the ionic radiopaque contrast agent, Renografin, was also studied and found to inhibit fibrin monomer assembly. Although iopamidol is not shown to be thrombogenic, iopamidol does appear to reduce platelet surface charge, bind fibrinogen, and modify fibrin clot structure.