ABSTRACT
Ancient materia medica and medical formularies were consulted to illustrate the development history of meridian-guiding theory of traditional Chinese medicine (TCM). The influences of various meridian-guiding drugs (Achyranthis Bidentatae Radix, borneol, Bupleuri Radix, Platycodon Radix) on the pharmacokinetic and pharmacodynamic characteristics of other drugs were summarized. Meridian-guiding drugs can promote the absorption and targeted distribution of other drugs and enhance the efficacy of injured tissues. The possible mechanisms of meridian-guiding are related with changing the component of cell membrane, inhibiting the efflux of P-gp, opening physiological barriers, modulating the levels of biochemicals, promoting microcirculation and adjusting the pH of targeted tissues. The chemical components of meridian-guiding drugs are the substance basis of meridian-guiding. The aim of exploring meridian-guiding chemicals is to find a natural targeted delivery system. At the present time, some progress has been made in the research on meridian-guiding field. However, further studies are required for the meridian-guiding theory of TCM.