咬合垂直距离降低后大鼠咬肌的酶组织化学定量研究  

Enzyme histochemical studies of the rat masseter muscle affected by decreased occlusal vertical dimension

作　　者：聂嘉[1] 于世宾[1] 何惠明[1] 

机构地区：[1]第四军医大学口腔医学院,硕士生陕西710032

出　　处：《口腔颌面修复学杂志》2010年第5期267-270,共4页Chinese Journal of Prosthodontics

摘　　要：目的:观察咬合垂直距离降低后大鼠咬肌酶组织化学特征的改变。方法:将40只雄性SD大鼠随机平均分为实验组与操作对照组,采用人为降低牙冠高度的方法降低实验组大鼠咬合垂直距离,实验开始3、10、30、60d时处死动物,取深层咬肌行辅酶Ⅰ-四氮唑还原酶(NADH-TR)染色,借助显微图像分析系统计算分析各型肌纤维的平均横截面积及百分构成比变化。结果:(1)大鼠深层咬肌由Ⅱa与Ⅱb两种肌纤维构成;(2)实验60天组大鼠Ⅱa型肌纤维平均截面积(mCAS-2a)明显小于实验3天组和同期操作对照组(P<0.05);(3)实验60天组Ⅱb型肌纤维平均截面积(mCAS-2b)明显大于实验3天组和同期操作对照组(P<0.05);(4)实验60天组Ⅱb型肌纤维所占百分构成比明显高于实验3天组与同期操作对照组(P<0.05)。结论:咬合垂直距离降低后大鼠咬肌发生了形态结构的功能适应性改建。Objective： To study the changes of the enzyme histochemical features of rat masseter induced by decreased occlusal vertical dimension（OVD）.Methods： 40 male SD rats were randomly divided into experimental group and sham-operated group.The crown height of the upper molars and the lower incisors was shortened mechanically to reduce the OVD.Five rats in experimental group and 5 age-matched controls,were sacrificed at the 3th,10th,30th and 60th day respectively.and the deep masseter muscles were excised.The enzyme histochemical staining（NADH-TR staining） was carried out on the sections of deep masseter muscle.The cross-sectional area of myofibers and fiber type propotion were analyzed by microscope image analysis system.Results：（1） The deep masseter musle consisted of type Ⅱa and Ⅱb myofibers.（2） The mean cross-sectional area of single Ⅱa fiber（mCSA-Ⅱa） in 60d experimental group was lower than that in 3d experimental group and its age-matched controls.（3） The mean cross-sectional area of single Ⅱb fiber（mCSA-Ⅱb） in 60d experimental group was higher than that in 3d experimental group and its age-matched controls.（4） The proportion of Ⅱb fiber in 60d experimental group was higher than that in 3d experimental group and its age-matched controls.Conclusion： The adaptive remodeling in rat masseter muscle was induced by the decreased OVD.

关 键 词：咬合垂直距离降低 咬肌 酶组织化学染色 肌纤维分布型 

分 类 号：R783.6[医药卫生—口腔医学]