CALCIFICATION MECHANISM OF THE OSTEOID IN THE PERIODONTAL LIGAMENT ON THE TENSION SIDE DURING TOOTH MOVEMENT.

采用未固定和未钙化的冰冻切片，对大鼠牙周韧带（张力侧）类骨进行元素分析（EPMA）和游离Ca^<2+>的检测。通过放射自显影检查Ca^<45>进入类骨。移动成年雄性大鼠上颌第一磨牙7天，用液氮固定上颌。制备未固定和未钙化的冷冻磨牙牙周韧带切片，进行组织学和组织化学（碱性磷酸酶活性：偶氮染色法）观察和EPMA检测。在游离钙检测中，在液氮冷冻固定前60秒从大鼠心脏注射荧光游离钙指示剂fluo-3。放射自显像方面，也在戊二醛灌注固定前60分钟腹腔注射Ca^<45>放射性同位素。然后对上颌进行放射自显影处理。颊周骨面…更多韧带（张力侧）呈波浪形，形成相当数量的类骨。在类骨层和成骨层可见强烈的ALP酶活性。类骨体上EPMA显示P和Ca的峰值极高，随着分析部位远离骨边缘，P和Ca的峰值先突然下降，然后逐渐下降。S和K在整个分析地点保持稳定的峰值。直线分析表明，P和Ca的变化是同步的，整个牙周间隙和牙髓腔都发出绿色荧光，表明游离Ca^<2+>的存在。类骨的荧光比牙周韧带的荧光更强烈。EPMA数据显示类骨钙的峰值高于牙周韧带。Ca^<45>在腹膜注射后60分钟深度沉积于颊周韧带（张力侧）的类骨中。这些结果表明，钙离子和钙离子在钙化过程中浓度升高，其浓度受到精确调控，钙离子由毛细血管供给，部分钙离子以离子形式存在于类骨中。少

Elemental analysis (EPMA) and detection of free Ca^<2+> were performed in the osteoid of the periodontal ligament (tension side) during the tooth movement in rats, using unfixed and undecalcified frozen sections. The uptake of Ca^<45> into the osteoid was examined by autoradiography.Upper first molars of mature male rats were moved seven days, and the upper jaws were fixed in liquid nitrogen. The unfixed and undecalcified frozen sections of the molar periodontal ligament were prepared for histological and histochemical (alkaline phosphatase activity : azo-dye method) observation and also for EPMA.In the detection of free-Ca, fluo-3, a fluorescent free Ca indicator, was injected from the hearts of the rats 60 sec.before freeze fixation by liquid nitrogen.In regard to the Autoradiography, Ca^<45> radioisotope was also injected intraperitoneally 60 min.before perfusion fixation of glutaraldehyde. Then the upper jaws were processed for Autoradiography.A bone surface in the buccal periodont … More al ligament (tension side) showed a wavy configuration, and a considerable amount of osteoid was formed. Intense ALP ase activity was noticed in the osteoid and osteoblastic layr. EPMA on the osteoid revealed extremely high peaks of P and Ca, that dropped a bruptly at first and then declined gradually, as the analyzed site moved away from the edge of the bone. S and K maintained steady peaks throughout the whole analyzed sites. Line analyzes demonstrated constant synchronization for the changes of P and Ca.Green fluorescence, showing the presence free Ca^<2+>, was emitted from the whole periodontal space and pulp cavity. The fluorescence from the osteoid was more intense than that from the periodontal ligament. EPMA data showed higher peak of Ca in the osteoid than in the periodontal ligament.Ca^<45> was deposited deeply in the osteoid of the buccal periodontal ligament (tension side) in 60 min.after the peritoneal injection.These results indicate that the osteoid concentration of P and Ca is elevated in the calcification and their concentration regulated precisely, and also that the Ca was supplied from the capillary, some of which is present in the form of ion in the osteoid. Less