ABSTRACT
The anatomical structure of acupuncture points is the carrier for needling stimulation induced neurobiological effects. Although researchers have never stopped investigating its structure and experienced different stages from macroscopic to microcosmic morphological material basis, our understanding still largely lags behind the requirements of the times. In the present paper, we review development of researches on acupuncture points in recent decades from 1) macroscopic anatomical structure including skin, bones, muscles, nerves, blood vessels, etc.; 2) macro-microcosmic structure as the thickness of skin and muscles, distribution of blood vessels and nerve fibers, and innervation; 3) microstructure including cell categories (mast cells, fibroblasts, macrophages, etc.), peptidergic nerve fibers, various receptors, chemical substances, and their relationship with the brain and immune-endocrine system (cutaneous-neuro-immune-endocrine-mental biological communication), etc. These research outcomes will not only help us demonstrate the acupoint's structure better at the level of the body surface and regional anatomy, but also, at the microstructural level, reveal different kinds of cells and their chemical compositions in its structure as well as their relationship with the regulatory system of the whole body. From the perspective of the cutaneous and systemic neuro-immuno-endocrine networks, it undoubtedly prompts us to profoundly explore the underlying biological mechanisms of acupuncture. To observe the regional mutual connection and interaction of different kinds of cells and their chemical mediators and molecules in the acupuncture point will improve our understanding about the nature of acupuncture points from the static to the dynamic point of view. This might be a new approach for us to further reveal the functional roles of acupuncture points.