Effect of Manual Acupuncture-Induced Injury on Rat Skeletal Muscle

ABSTRACT Background: Muscle injury stimulates normal quiescent resident satellite (stem) cells to re-enter the cell cycle and execute the myogenic program, resulting in muscle fiber regeneration. We hypothesized that part of acupuncture's efficacy is a consequence of needle-induced injury that stimulates satellite cells within muscle tissue. Objective: To determine whether manual acupuncture needling on a single point (ST 36) in a rat model can produce focal muscle damage and activate satellite cells. Design and Setting: Four male Sprague-Dawley rats were studied in this experiment at a single US academic institution. Intervention: The rats were anesthetized and underwent needling at ST 36 in the tibialis anterior (TA) muscle. Main Outcome Measure: Assessment of TA muscle damage was determined using light microscopy. Immunofluorescence was used to detect MyoD antibody, and Western blot to determine MyoD protein. Results: Phenotypic and morphological changes associated with focal injury were demonstrated. ...