Three-dimensional visualization of interstitial channels in the limbs of mini-pigs and a comparison with human meridians
Meridians are a central concept in traditional Chinese medicine theory.Previous studies have indicated the presence of long-range fluid flow within interstitial spaces,potentially associated with meridians.In our prior research,by injecting a small-molecule fluorescent substance with tissue affinity into low impedance points(LIPs)along meridians in the limbs of mini-pigs,we observed partial fluorescence trajectories along the meridians on the body surface.Anatomical examination revealed that the primary trajectory of migration lay within the deeper layers of interstitial tissue.To compare these deep trajectories with those of human meridians,in this study,we initially located LIPs on the limbs of eight healthy mini-pigs using a meridian locator.Subsequently,six of these pigs underwent injections along 12 low-resistance meridian lines(one per leg),and the last one was marked according to human bone measurement standards for cross-sectional positioning.After injecting a trace amount of fluorescein sodium(FS)into the LIPs and adjacent high-impedance points,excess anaesthetics were injected,and the limbs were frozen.Following removal and embedding of the frozen limbs,cross-sections were obtained using an electric bone saw.Bright-field and fluorescence images of the cross-sections were captured using a digital camera equipped with a narrowband filter and blue laser illumination to observe the distribution characteristics of the fluorescence signals on the cross-sections.Fresh cross-sectional tissue cryosections were prepared from the fluorescent area for microscopic structural observation.Images from consecutive cross-sections were used for three-dimensional reconstruction of the migration trajectory.The results revealed replicable trajectories on the cross-sections after FS injection at the LIPs in the limbs,showing 12 distinct migration trajectories.Except for the convergence of three yin meridians on the medial side of the forelimb towards the proximal end,the remaining channels remained independent and fixed in position.Nonmeridian injections exhibited limited ellipsoidal diffusion or continued migration along adjacent interstitial channels after spreading.The positions of the fluorescence signals on the cross-sections closely matched the traditional descriptions of meridian pathways in traditional Chinese medicine,aligning well with acupuncture needle positions.Microscopically,the structure appeared as a network of fibrous gaps within the connective tissue.This research highlights the existence of long-range continuous interstitial channels within living organisms,potentially constituting one aspect of the scientific essence of traditional Chinese medicine meridians.
万方数据
维普
