Effects of electroacupuncture on gait and proliferation and differentiation of muscle satellite cell in rats with acute blunt trauma of gastrocnemius muscle / 中国针灸

OBJECTIVE@#To observe the effects of electroacupuncture on threshold of pain, gait, proliferation and differentiation of muscle satellite cell in rats with acute blunt trauma of gastrocnemius muscle, and to explore the possible mechanism of electroacupuncture in promoting the repair of acute injury of skeletal muscle.@*METHODS@#A total of 48 SD rats were randomly divided into a blank group (6 rats), a model group (24 rats) and an electroacupuncture group (18 rats). In the model group and the electroacupuncture group, the model of acute blunt trauma of gastrocnemius muscle was established by self-made impactor. In the electroacupuncture group, electroacupuncture was applied at "Chengshan" (BL 57) and "Yanglingquan" (GB 34) on the right side, with disperse-dense wave, in frequency of 2 Hz/100 Hz, once a day, 30 min each time. Electroacupuncture intervention was performed for 3, 7 and 14 days according to the sampling time. On the 1st, 3rd, 7th and 14th days after modeling, the mechanical withdrawal pain threshold of hindfoot was detected by Von Frey method; the standing time and the maximum contact area of the right hindfoot were recorded by Cat Walk XTTM animal gait analysis instrument; the morphology of the right gastrocnemius muscle and the number of inflammatory cells were observed by HE staining; the positive expression of paired box gene 7 (Pax7) and myogenic differentiation (MyoD) of the right gastrocnemius muscle was detected by immunofluorescence.@*RESULTS@#After modeling, the muscle fiber rupture and massive infiltration of red blood cells and inflammatory cells were observed in the right gastrocnemius muscle; after electroacupuncture intervention, the morphology of muscle fiber was intact and the infiltration of inflammatory cells was improved. Compared with the blank group, in the model group, the differences of mechanical withdrawal pain threshold between the left and right foot were increased (P<0.05), the standing time was shortened and the maximum contact area of the right hindfoot was decreased (P<0.05), the number of inflammatory cells and the positive expression of Pax7 and MyoD of the right gastrocnemius muscle were increased (P<0.05) on the 1st, 3rd, 7th and 14th days after modeling. Compared with the model group, in the electroacupuncture group, the differences of mechanical withdrawal pain threshold were decreased (P<0.05), the standing time was prolonged (P<0.05), the number of inflammatory cells of right gastrocnemius muscle was decreased (P<0.05) on the 7th and 14th days after modeling; the maximum contact area of the right hindfoot was increased (P<0.05), the positive expression of MyoD of the right gastrocnemius muscle was increased (P<0.05) on the 3rd, 7th and 14th days after modeling; the positive expression of Pax7 of the right gastrocnemius muscle was increased (P<0.05) on the 3rd day after modeling.@*CONCLUSION@#Electroacupuncture can effectively improve the pain threshold and gait in rats with acute blunt trauma of gastrocnemius muscle, and promote the repair of skeletal muscle injury, the mechanism may be related to the up-regulation of Pax7 and MyoD, so as to promoting the proliferation and differentiation of muscle satellite cell.

Effects of Yunnan Baiyao on inflammatory response and satellite cell regeneration after acute injury of skeletal muscle in rats / 吉林大学学报(医学版)

Objective To study the effects and mechanism of Yunnan Baiyao on the inflammatory response and satellite cell regeneration after acute injury of skeletal muscle in rats. Methods Rat models of skeletal muscle injury (gastrocnemius,fast twich;soleus,slow twich) induced by treadmill were constructed 24 h after establishment of the models,the left sides of hind limbs in rats were treated with Yunnan Baiyao,and the right sides were treated with saline at the equal volume.4 rats were chosen 2,4,7,10,14 d after injury,respectively,and gastrocnemius and soleus of the treated sides (the left sides) and untreated sides (the right sides) from hind limbs of 4 rats were obtained,and stained with immunohistochemistry and HE. The quantity and morphological changes of inflammatory cells and satellite cells were observed under optical microscope. Results Compared with untreated sides,the number of inflammatory cells of fast twich after injury in the treated sides was decreased obviously at the 2nd,4th,7th day after injury(P