Effects of contrast media on endothelial cell monolayers under controlled flow conditions.

To compare the biocompatibility of nonionic and ionic intravascular contrast media in a more physiologic in vitro system, key aspects of blood flow through a microvessel were simulated. Toward this end, monolayers of endothelial cells placed in a specially designed flow chamber, real-time imaging of the monolayers by brightfield and phase videomicroscopy, and real-time imaging and computer-aided quantitation at normal hematocrit levels of platelet adhesion/aggregation to sites of monolayer injury by means of epifluorescence videomicroscopy were used. At a concentration in culture medium of 20% by volume, it was found that monolayer morphology was least altered by iohexol when compared with diatrizoate and ioxaglate; monolayer production of prostacyclin was enhanced (p less than 0.001) by ioxaglate compared with saline controls; and at a concentration in citrated blood of 20% by non-red-cell volume, platelet adhesion/aggregation was reduced by all 3 contrast agents in the order diatrizoate greater than ioxaglate greater than iohexol.