title: Contrast medium attenuates platelet activation and platelet-leukocyte cross-talk.
abstract: The influence of ionic and non-ionic contrast media (CM) on platelet and leukocyte activation and platelet-leukocyte crosstalk was investigated in hirudinized whole blood. The blood was incubated with and without the ionic CM ioxaglate and the nonionic CM iodixanol at 37 degrees C for 5 min, without or with stirring. Platelet and leukocyte activation and platelet-leukocyte aggregation were measured using whole blood flow cytometry. When blood samples were pre-incubated in the presence of 2%, 5%, and 10% of CM without stirring, both ioxaglate and iodixanol had little effect on unstimulated samples, but dose-independently decreased 1 microM ADP-induced platelet P-selectin expression and fibrinogen binding, and thus platelet-leukocyte aggregate formation. Ioxaglate had little effect on leukocyte CD11b expression, whilst iodixanol slightly enhanced resting and N-formyl-methionyl-leucyl-phenylalanine (fMLP; 0.1 microM)-stimulated leukocyte CD11b expression. Blood samples were also incubated with stirring to investigate the impact of CM (5% of ioxaglate or iodixanol) on platelet-leukocyte cross-talk. Collagen induced marked platelet activation and platelet-leukocyte aggregation, and subsequently elevated leukocyte CD11b expression. The latter was attenuated by ioxaglate and iodixanol, and was accompanied by reduced platelet-leukocyte aggregation. In conclusion, the CM ioxaglate and iodixanol attenuate platelet activation and platelet-leukocyte cross-talk. Inhibitory effects of the contrast agents on this cross-talk are apparently exerted by reducing heterotypic conjugation, and may be beneficial in connection with PCI.
authors.affiliation: Department of Medicine, Clinical Pharmacology Unit, Karolinska University Hospital (Solna), Stockholm, Sweden.
authors.forename: Qiushang
authors.initials: Q
authors.lastname: Ji
authors.forename: Melania
authors.initials: M
authors.lastname: Ghaly
authors.forename: Paul
authors.initials: P
authors.lastname: Hjemdahl
authors.forename: Per
authors.initials: P
authors.lastname: Tornvall
authors.forename: Nailin
authors.initials: N
authors.lastname: Li
mesh_terms: D000244:Adenosine Diphosphate / Q000737:chemistry; D000328:Adult; D001792:Blood Platelets / Q000166:cytology*; D039481:CD11b Antigen / Q000096:biosynthesis; D002450:Cell Communication; D003287:Contrast Media / Q000494:pharmacology*; D005260:Female; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D007477:Ions; D007485:Ioxaglic Acid / Q000494:pharmacology; D007962:Leukocytes / Q000166:cytology*; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000378:metabolism; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D015539:Platelet Activation; D010973:Platelet Adhesiveness; D014283:Triiodobenzoic Acids / Q000494:pharmacology
chemical_list: D039481:CD11b Antigen; D003287:Contrast Media; D007477:Ions; D014283:Triiodobenzoic Acids; D009240:N-Formylmethionine Leucyl-Phenylalanine; D000244:Adenosine Diphosphate; C044834:iodixanol; D007485:Ioxaglic Acid