Fig. 2.

NOergic molecules and neuropeptides mediated stimuli-evoked peripheral axon reflexes involved in sensory signal transduction of propagated signals along channel pathways (PSCP) and morphological studies of acupoints along the skin meridian. The top panels show a somatosensory line path along the acupoints and meridian after a stimulus applied on a distal acupoint. The bottom panel shows anatomical studies of acupoints/meridians which exist higher number of nerve fibers/trunks, blood vessels, hair follicles, and sweat glands compared to their control areas without meridian. The higher number of small nerve fibers, blood vessels with rich endothelia and neuronal NO synthase, TRPV1 and neuropeptides such as calcitonin gene related peptide, and sweat glands in the cutaneous tissues serve as structures for NO signaling molecules and neuropeptides mediated axon reflexes with signal functions.