ABSTRACT
Objective:To explore the effects and mechanism of electroacupuncture (EA) on expression of myostatin (MSTN), muscle-specific ring finger protein 1 (MuRF1/Trim63), F-box only protein 32 (Atrogin-1/ Fbxo32), myogenic differentiation antigen (Myod) and myogenin (Myog) in traumatic spinal cord injury (TSCI) rats. Methods:A total of 45 adult female Sprague-Dawley rats were randomly divided into sham operation group (n = 12) and operation group (n = 33). The TSCI model was established with the modified Allen's method. After modeling, there were 24 survival rats and they were randomly divided into model group (n = 12) and EA group (n = 12). EA group was electroacupunctured at Dazhui (DU 14), Mingmen (DU 4) and bilateral Zusanli (ST 36) for 10 minutes, once a day, six times a week for 28 days. Basso-Beattie-Bresnahan (BBB) score was tested before modeling, and three days, seven days, 14 days, 21 days and 28 days after modeling. The rats were measured their body mass before and 28 days after modeling. The ratio of gastrocnemius wet mass was calculated; the cross-sectional area (CSA) and fiber diameter were measured by HE staining; the expression of MSTN, Trim63, Fbxo32, Myod and Myog mRNA were tested with real-time quantitative polymerase chain reaction (qPCR). Results:Three days, seven days, 14 days, 21 days, and 28 days after modeling, the score of BBB was lower in the model group than in the sham operation group (P < 0.01); seven days, 14 days, 21 days, and 28 days after modeling, the score of BBB was higher in EA group than in the model group (P < 0.01). Compared with the sham operation group, the mass of rats, the gastrocnemius wet mass, the CSA and the diameter of the muscle fiber were smaller in the model group (P < 0.05), while the expression of MSTN, Trim63, Fbxo32, Myod and Myog mRNA were higher (P < 0.05). Compared with the model group, the mass of rats, the gastrocnemius wet mass, the CSA, the expression of Myod and Myog mRNA were higher (P < 0.05) in EA group, while the expression of MSTN, Trim63 and Fbxo32 mRNA were lower (P < 0.05). Conclusion:EA might delay the gastrocnemius atrophy in TSCI rats by down-regulating the expression of MSTN, Trim63, Fbxo32 mRNA and up-regulating the expression of Myod and Myog mRNA via controlling the differentiation of the muscle satellite cells and the degradation of protein in skeletal muscle cells.
ABSTRACT
Objective To isolate and culture sweat gland epithelial cells in vitro,and to study the effects of acetylcholine (ACh) on intracellular flee calcium concentration ([Ca~(2+)]i) of cultured sweat gland epithelial cells.Methods Sweat glands epithelial cells were collected by enzymatic digestion.After ACh was added to the primary and first passage cells,[Ca~(2+)]i was examined using confocal laser scanning microscopy (CLSM) and the Ca~(2+) sensitive dye Fura 3/AM.Results The primary and first passage epithe- lial cells grew well.After ACh was added,opening of the calcium channel and significant [Ca~(2+)]i increase were observed when the primary and first passage cells were incubated with high concentration of calcium (2 mmol/L);no significant [Ca~(2+)]i increase was observed in those cultured without calcium.Conclusion Upon stimulation with ACh,calcium channels of cultured primary and first passage sweat gland epithelial cells would open,influx of extracellular Ca~(2+) occurred,which resulted in an increase of [Ca~(2+)]i.Extracellular bound calcium was therefore converted into intracellular free calcium.