Effect of iodinated contrast media on the synthesis and metabolism of leukotriene B4.
To investigate whether the endogenous vasoactive substrate, leukotriene B4 (LTB4), was induced in adverse reactions observed after intravenous injection of iodinated contrast media (CM), the authors measured the in vitro production and metabolism of LTB4 by human polymorphonuclear leukocytes (PMNs) after stimulation with different doses of commercial CM preparations: iopamidol, 300 mg I/mL; iodamide, 300 mg I/mL; iohexol, 300 mg I/mL; ioxaglate, 320 mg I/mL; and the experimental preparation, iomeprolo. This study showed that the CM studied do not stimulate the production or metabolism of LTB4 by isolated human blood PMNs. All of the CM studied except iodamide do not inhibit the production or metabolism of LTB4 in PMNs stimulated by A23187. The in vitro hepatic microsomal oxidation of exogenous LTB4 to (omega-1)OH LTB4 and omega-OH LTB4 was inhibited by all the CM studied. LTB4 production by PMNs seems not to play a major role in anaphylactoid reactions observed after iodinated CM. However, a transient blockade by CM of LTB4 metabolism, leading to an increase of steady-state concentrations of LTB4, could not be excluded by these experiments.
Romano
M
M
Istituto di Recerche Farmacologiche Mario Negri, Milano, Italy.
Di Bello
M
M
Salmona
M
M
Piovani
B
B
Rosati
G
G
D000818:Animals; D003287:Contrast Media / Q000494:pharmacology*; D006801:Humans; D007451:Iodamide / Q000494:pharmacology; D007472:Iohexol / Q000494:pharmacology; D007479:Iopamidol / Q000494:pharmacology / Q000031:analogs & derivatives; D007485:Ioxaglic Acid / Q000494:pharmacology; D007975:Leukotriene B4 / Q000096:biosynthesis / Q000378:metabolism*; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008862:Microsomes, Liver / Q000201:enzymology / Q000378:metabolism; D009504:Neutrophils / Q000378:metabolism
D003287:Contrast Media; C057937:iomeprol; D007975:Leukotriene B4; D007472:Iohexol; D007451:Iodamide; D007479:Iopamidol; D007485:Ioxaglic Acid