Abstract
It was pointed out in the two earlier papers of the present author that the meridians are in fact zones in the loose connective tissue containing richer interstitial fluid and thus are lower-resistance passages for diffusion of meridian-signal carriers or mediators. Moreover, a hypothesis, which incorporates the wide variety of functions of the loose connective tissue, the circulatory system, and the nervous system into the meridian function, has been proposed and in the hypothesis the mast cell plays some key roles. In the present paper, considering also the latest knowledge on cell migration along with some existing experimental results, it is further pointed out that meridians ought to be lower-resistance passages for chemotactic migration of cells and mast cells can indeed migrate longitudinally along meridians. Finally, the present paper points out that if we add the last two points to the hypothesis and keep in mind that mast cells have been known very recently to be versatile regulators of inflammation, tissue remodeling, host defense, and homeostasis, the rich pathophysiological functions of the meridian pointed out by the traditional Chinese medicine can be understood quite naturally.