Endothelial cell injury and platelet aggregation induced by contrast ultrasonography in the rat hepatic sinusoid.

Abstract

To determine whether contrast ultrasonography can affect the sinusoidal cells and platelets of the liver by using ultrastructural analysis in vivo. Fifteen Wistar rats were placed into the following 5 groups of 3 rats each: 3 control groups comprising a sham operation group, a contrast agent injection-alone group, and an ultrasound exposure-alone group; and 2 contrast agent injection with ultrasound exposure groups, split according to excision time. After a dose of an echo contrast agent (100 mg/kg of body weight) was administered through the femoral vein, the rats that received injections were subjected to ultrasound for the first minute, no ultrasound for the next 4 minutes, and then ultrasound sweep scanning for 10 seconds. The rats were perfused via the heart with cold physiologic saline containing 2% paraformaldehyde and 2.5% glutaraldehyde solution buffered with 0.1-mol/L phosphate. The livers of the rats in 4 of the groups were excised immediately. The livers of the rats in 1 of the 2 contrast agent with ultrasound exposure groups were excised by the same procedure 5 hours after they received the injections. All specimens were studied with light and electron microscopy. Platelet aggregation and injury to endothelial cells were more severe in the contrast agent injection and ultrasound exposure groups than in the other groups. Contrast ultrasonography can cause platelet aggregation and endothelial cell damage in the rat hepatic sinusoid.