Visualization Study of Interstitial Channels in Rat Limb Segments and Comparison with Acupoint Positions

SHEN Yaohua; WANG Yanping; XIONG Feng; SONG Xiaojing; JIA Shuyong; WANG Guangjun; WANG Shuyou; GU Shuya; ZHANG Weibo

Abstract：Objective To visualize the interstitial channels along meridians(ICM)in rats adopted whole cross-section combined with fluorescence photography,and to provide imaging evidence for the theory of interstitial channel.Methods 14 male SD rats were randomly divided into stomach meridian group and bypass group,with 7 rats in each group.The concentration of 1%sodium fluorescein(SF)solution was injected into the low resistance points and the side non-low resistance points of the stomach meridian of the two groups of rats respectively.The rats were killed 5 minutes after injection,placed in a mold,and integral embedding was performed with 5%gelatin solution.After freezing overnight at-80℃,the rats were continuously cross-section with an electric bone sawing machine,and the bright field and fluorescence images of the cross-section were collected to observe the distribution of tracers in the limbs.The position of fluorescence signal on the limb cross-section was compared with that of conventional acupuncture points.Results There was a significant long-term migration track in the interstitial structure after injection of SF in the stomach meridian group,while SF only diffused locally at the injection point in the bypass group,and the migration length of tracers between the two groups was statistically significant(P<0.01).The position of the fluorescence signal on the cross-section of the limb is within the anatomical level reached by the tip of the needle in the main acupoint of the human stomach.Conclusion The long-term migration of the tracer in the deep interstitial of the limb can be observed after the injection of SF in the low resistance points of the limbs of rats.The position of the tracer in the cross-section highly coincides with the position of insertion of the human meridian point into the body,which provides new evidence for the"meridian interstitial channel theory"and provides a new idea for the visualization of the meridian.