[Investigation in vivo of effect of ultrasound-mediated microbubble destruction on entrance of feridex into the aortal wall].

OBJECTIVE

To explore feasibility for entrance of the contrast agent Sonovue and Feridex into the aortal wall.

METHODS

17 male Japanese giant ears rabbits (common grade), including 11 atherosclerosis (AS) animal models fed with food containing high-content lipid and normal animals fed with common food as control. Respectively, 10 animals in the AS group and 6 animals in the normal group were selected in a random way to undergo ultrasound-mediated microbubble destruction (UMMD) and no ultrasound-mediated microbubble destruction (-UMMD) half and half. One animal was administrated with double doses of Feridex. After general anesthesia, MR plain scan and intravenous injection of Feridex 100 micromol Fe/kg, immediately ultrasound focused on the front wall of the aortic arch, which underwent UMMD at the pressure of 3.5 Mpa with MI1.2 while 10 ml solution (Sonovue + normal saline)was injected intravenously at the speed of 0.5 ml/min FOR 20 min. 3T magnetic resonance (MR) was performed with a moderately T2* weighted gradient sequence. Enhanced scan were performed for 1 h, 24 h, 48 h, 72 h and after killing the animal. then the specimen were delivered to conduct optical and electronic microscope examination. Variance test for the re-measured data was adopted to verify the data obtained in every group.

RESULTS

The effect of UMMD group on SPIO particles entrance into the aortal wall is of marked significance (P = 0.0004) statistically. The effect of UMMD on distribution in the vessel wall is of statistical significance (P = 0.01), more particles in the dventitia. Gas or microbubbles were found to enter into the intima, media of the aorta, and verified by Oil Red O staining. After staining the findings of iron particle in the cell and out of the cell are different.

CONCLUSIONS

UMMD may facilitate entrance of those SPIO particles with a bigger diameter and microbubbles into the aortal wall. This discovery may provide a new solution for penetration of complex macromolecule probes and gene-carried drug through the tunica intima of the aorta.