作　　者： (）;

机构地区： 暨南大学口腔医学院

出　　处： 《南方医科大学学报》 2018年第6期755-760,共6页

摘　　要： 目的探明咬合干扰作用下大鼠咬肌组织线粒体钙离子浓度与细胞外钠离子浓度的变化特点,探讨钙调蛋白激酶Ⅱ(Ca MKⅡ)对线粒体"钙超载"现象的调控机制。方法在SD大鼠右侧上颌第一磨牙咬合面粘接直径0.6 mm钢丝段,建立咬合干扰大鼠模型,实验组分为3、7、14、21 d及去除咬合干扰后3 d组,并设立对照组。应用苏木精-伊红(HE)染色法观察咬肌组织形态学的变化;应用荧光分光光度法检测咬肌线粒体钙离子浓度;应用6-氢氧化锑钾直接比浊法检测咬肌肌纤维细胞外钠离子浓度;应用Western blotting技术检测咬肌组织p-Ca MKⅡ(Thr286)/Ca MKⅡ表达水平。结果与对照组比较,建模3、7、14和21 d实验组咬合干扰侧咬肌线粒体Ca2+浓度持续升高(P<0.05),去除咬合干扰后3 d组Ca2+浓度显著下降且低于正常对照组(P<0.05)。建模3 d组、7 d组、14 d组及21 d组细胞外Na+浓度持续升高(P<0.05),去除咬合干扰后3 d组Na+浓度显著降低(P<0.05)。建模3 d、7 d和14 d实验组咬合干扰侧p-Ca MKⅡ(Thr286)/Ca MKⅡ表达水平持续升高(P<0.05),但其表达水平在建模21 d组下降且低于对照组水平(P<0.05),去除干扰3 d组表达水平显著下降且低于21 d组(P<0.05)。非咬合干扰侧变化趋势同干扰侧趋势一致,但干扰侧变化更显著(P<0.05)。结论咬合干扰可使大鼠咬肌线粒体Ca2+和胞浆Na+浓度升高,引发"钙超载";线粒体Ca2+浓度升高与Ca MKⅡ磷酸化水平相关,提示其对线粒体"钙超载"具有负反馈调节作用。 Objective To investigate the changes in mitochondrial calcium and extracellular sodium concentrations in the masseter muscle of rats with occlusal interference and the regulatory mechanism of mitochondrial Ca2＋overload by calmodulin kinase II（Ca MK II）. Methods SD rat models of occlusal interference were established by placing a stainless steel segments（0.8 mm in diameter） to raise the occlusal surface of the upper right first molar. At 3, 7, 14, and 21 days after occlusal interference and at 3 days after removal of occlusal interference, HE staining was used to observe the histomorphological changes of the masseter muscle. Mitochondrial calcium concentration in the masseter muscle was detected using fluorescence spectrophotometry, and direct turbidimetry with potassium pyroantimonate was used to detect the extracellular sodium concentration; the expression levels of masseter muscle p-Ca MK II（Thr287） and Ca MK II were detected using Western blotting. Results Compared with those in the corresponding control groups, mitochondrial Ca2 ＋concentration in the masseter muscle on occlusal interference side increased significantly at 3, 7, 14 and 21 days after occlusal interference（P〈0.05）, but was significantly lowered at 3 days after removal of the interference（P〈0.05）. The concentration of extracellular Na＋increased progressively with time at 3, 7, 14 and 21 days after occlusal interference（P〈0.05）, and was significantly decreased at 3 days after interference removal（P〈0.05）. Occlusal interference for 3, 7 and 14 days resulted in significantly increased expressions of p-Ca MK II（Thr287） and Ca MK II（P〈0.05）, which was significantly decreased at 21 days compared with those in the control groups（P〈0.05） and further decreased after removal of occlusal interference（P〈0.05）. Similar changes were also observed on the side without interference, but the changes on the interference side were more obvious（P〈0.05）. Conclusion Occlusal interference causes eleva

关 键 词： 线粒体钙超载 咬合干扰 咬肌 钙调蛋白激酶 咀嚼肌功能紊乱

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