液压扩张后动脉内膜及平滑肌的厚度变化与临床意义

THE THICKNESS CHANGE AND CLINICAL SIGNIFICANCE OF TUNICA INTIMA AND SMOOTH MUSCLE IN ARTERY AFTER HYDROLIC DILATION

目的 探讨液压扩张后动脉内膜及平滑肌厚度的变化与临床意义。方法 用 0、40、80及12 0 k Pa压力的等渗盐水对新西兰大白兔 (A组为对照组 ,B、C、D组为实验组 )右侧颈总动脉进行液压扩张 ,用自动图像分析系统对动脉扩张后即刻、1周及 2周管径、平滑肌及内膜的厚度进行测量。结果 动脉液压扩张后即刻和1周时 ,实验组血管直径均大于对照组 ,有非常显著性差异 (P<0 .0 1) ;2周时 ,B、D组与 A组比较无明显差异 (P>0 .0 5 ) ,C组较 A组明显扩大 ,有非常显著性差异 (P<0 .0 1)。动脉液压扩张后即刻 ,实验组平均平滑肌和内膜联合厚度与对照组比较无显著性差异 (P>0 .0 5 ) ;1、2周时 ,A组与 B组比较无显著性差异 (P>0 .0 5 ) ,C、D组均大于 A组 ,有非常显著性差异 (P<0 .0 1)。液压扩张 2周后 B组动脉内膜无明显增厚 ,C组动脉内膜增厚 ,D组动脉内膜明显增厚。结论 不同压力的液压扩张可使动脉管径增大 ,但超过 80 k Pa的压力可导致平滑肌、内膜的增厚 ,故动脉液压扩张的压力以不超过 40 k

Objective To study the proliferation change of tunica intima and smooth muscle in artery after hydrolic dilation for potential clinical use. Methods Sixten adult New Zealand rabbits were randomly divided into 4 groups, named group A, B, C and D. Right carotid arteries of rabbits of those 4 groups were dilated by hydrolic dilation with different pressures with 0 kPa, 40 kPa, 80 kPa, and 120 kPa respectively. The arterial calibers, thickness of tunica intima and smooth muscle were analyzed by automatic medical photograph analyzer immediately, 1 week and 2 weeks later respectively. Results\ The arterial calibers in the experimental group were larger than those in control group after immediate hydrolic dilation and 1 week later ( P< 0.01). At 2 weeks, the arterial calibers in group B and D has no significant difference compared to group A ( P> 0.05), and those in group C were larger than that of group A ( P< 0.01). There were no significant difference in thickness of tunica intima and smooth muscle between the experimental group and control group ( P> 0.05) after immediate hydrolic dilation. At 1 and 2 weeks after dilation, there were no significant difference between group A and group B ( P> 0 05), and those in group C and D were all larger than those in group A ( P< 0.01). No obvious proliferation of tunica intima were observed in group B at 2 weeks after hydrolic dialation, but the proliferation of tunica intima could be observed in group C and D, especially in group D. Conclusion Caliber of artery can be expanded by hydrolic dilation with higher pressure, but the proliferation of tunica intima and smooth muscle may be occured in hydrolic dilation with pressure over 80 kPa, therefore it is safe to use hydrolic dilation with pressure no more than 40 kPa.