ACID PHOSPHATASES IN DEVELOPING BONES AND TEETH

拟议项目的总体目标是描述和 在发育中的骨骼和釉质器官中定位酸性磷酸酶， 牙髓的牙芽，并确定甲状旁腺激素的影响， 维生素D在体内/体外对不同的磷酸酶，以获得 这些酶在硬组织形成中的作用， 功能 大鼠组织匀浆中的酸性磷酸酶已被 通过柱层析进行不同程度的分离纯化。 酶的表征将在分子水平上完成。 尺寸、最适pH值、热不稳定性、各种 底物和各种效应物对动力学的影响 特征。 关于各种酸的功能的信息 磷酸酶将通过测定（a）磷酸酶的特异性来获得。 （B）酶在体内的定位 细胞和细胞器，以及（c）通过测定维生素 D和甲状旁腺素对特异性酸活性和组织水平的影响 体内骨和牙芽中以及体外培养骨中的磷酸酶。 后一项研究将在维生素D缺乏的哺乳动物中进行 大鼠，或者，对于体外实验，用骨或分离的骨细胞 这样的老鼠。 酶的定位将通过以下方法确定： (a)对主要含有一种类型的解剖组织的生化研究 （B）光镜和电镜下的细胞化学技术 使用特定底物和抑制剂以生物化学方式测定的水平; 和（c）免疫细胞化学技术，使用抗一种或多种 特异性磷酸酶。

The overall objective of the proposed project is to characterize and localize the acid phosphatases in developing bones and the enamel organ and pulp of tooth buds and to determine the effect of parathyroid hormone and vitamin D in vivo/in vitro on the different phosphatases, in order to gain insight into the role of these enzymes in hard tissue formation and function. The acid phosphatases in rat tissue homogenates have been separated and purified to differnet degrees by column chromatography. Characterization of the enzymes will be completed with regard to molecular size, pH optimum, thermolability, kinetic characteristics for various substrates and the influence of various effectors on the kinetic charactristics. Information concerning the function of the various acid phosphatases will be obtained by determining (a) the specificity of the enzymes for potential in vivo substrates; (b) localization of enzymes in cells and cellular organelles and (c) by determining the effect of vitamin D and parathyroid hormone on activity and tissue level of specifici acid phosphatases in bone and tooth buds in vivo and in bone cultured in vitro. The latter studies will be carried out with vitamin D-deficient suckling rats, or, for the in vitro experiments, with bones or isolated bone cells from such rats. Localization of the enzymes will be determined by means of (a) biochemical studies on dissected tissues containing primarily one type of cell; (b) cytochemical techniques at the light and electron microscopic levels using specific substrates and inhibitors determined biochemically; and (c) immunocytochemical techniques using antiserum to one or more specific phosphatases.