比较脂质微泡与聚合物超声造影剂的微循环流变学

目的 探讨脂质微泡与高分子聚合物超声造影剂在大鼠肠系膜微循环中的流变学特征。方法 对10只大鼠经股静脉分别注射DiI标记的脂质微泡和高分子聚合物超声造影剂,通过倒置荧光显微镜观察两种不同造影剂在大鼠肠系膜微循环中的运动情况;比较注射前后小动脉、小静脉及毛细血管内径的变化,测定红细胞与两种造影剂在微循环内的流速。结果 注射后两种造影剂在大鼠肠系膜微循环内均可随血流移动,仅见少量脂质微泡短暂滞留。注射造影剂前后小动脉、小静脉及毛细血管内径无明显改变(P>0.05);两种造影剂在微循环内的流速与红细胞相似,差异无统计学意义(P>0.05)。结论 脂质微泡和高分子聚合物超声造影剂具有与红细胞相似的微循环流变学特征,均可作为红细胞示踪剂。

Comparison on microvascular rheology between lipid- and polymer-shelled ultrasound contrast agents

Objective To investigate the microvascular rheology characteristics of lipid- and polymer-shelled ultrasound contrast agents in mesentery microcirculation of rats. Methods DiI-stained lipid- and polymer-shelled ultrasound contrast agents were prepared. After injection of the two contrast agents from the femoral vein of 10 rats, the microvascular rheology of the contrast agents in the mesentery microcirculation were observed under the inverted fluorescence microscope. The diameter of the arterioles, venules and capillaries before and after injection were compared. The velocity of the red blood cells and the contrast agents were measured. Results The contrast agents could move with the blood flow in the microcirculation. Only transient retention of few lipid microbubbles was observed in the venules. After injection of the contrast agents, the diameter of the arterioles, venules and capillaries had no significant difference (P>0.05). The velocity of the red blood cells and the two contrast agents had no significant difference (P>0.05). Conclusion Lipid- and polymer-shelled contrast agents have similar microvascular rheology characteristics with red blood cells, both can be used as tracers of red blood cells.