Morphological and functional abnormalities in platelets exposed in vitro to ioglicinic acid, a new ionic contrast medium.

The inhibitory effect on platelet function induced by several radiographic contrast media is still poorly understood. In this study platelet abnormalities caused byin vitro addition of ioglicinic acid, a new ionic contrast medium, were evaluated. The appearance of several granules similar to dense bodies associated with shape change and internal reorganization were detected by electron microscopy techniques. A functional study revealed a marked decrease in the aggregating response of platelets to adenosine diphosphate and calcium ionophore A23187, while aggregation in response to collagen was completely normal. It is suggested that ioglicinic acid induces platelet abnormalities related to the effect on calcium movements and that studies with this contrast medium may help the understanding of some basic events of platelet activation.