Morphologic endothelial response to meglumine diatrizoate: an electron-microscopic study.

Ultrastructural changes in vascular endothelium after an intra-aortic injection of 65% meglumine diatrizoate, 10 ml/kg, and equiosmolal hypertonic saline were observed using electron microscopy in the rat. Cell shrinkage and expansion of intercellular clefts were found in all specimens from a large artery at 5 and 20 minutes after injection. Some destroyed cells were seen at all times after contrast and hypertonic saline administration, but one-half of the specimens taken at 1 hour were otherwise nearly normal in appearance. In muscle capillaries, the changes were less severe than in the large artery. Despite the large dose, equiosmolal meglumine diatrizoate and saline solutions produced identical vascular lesions as detected with electron microscopy.