The central part of parathyroid hormone stimulates thymidine incorporation of chondrocytes.
The central part of parathyroid hormone stimulates thymidine incorporation of chondrocytes.
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甲状旁腺激素的中心部分刺激软骨细胞的胸苷掺入。
DOI：
10.1016/s0021-9258(18)60431-4
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Hubert MayerS
中科院分区：
文献类型：
--
作者：
Klaus;H. Hellstern;Edgar Wingender;Hubert MayerS
通过测定[3H]胸腺嘧啶并入DNA，研究甲状旁腺激素对鸡软骨细胞原代培养细胞DNA合成的刺激作用。通过改变细胞年龄、镀层密度和孵育时间来确定最佳检测条件。在这些条件下，甲状旁腺激素（PTH）及其部分片段显著刺激DNA合成：用人(h)PTH（1-84）、牛(b)PTH（1-34）和[Nle8,18,Tyr34]bPTH（3-34）酰胺和hPTH（13-34）处理的细胞显示出2.6倍的[3H]胸腺嘧啶结合，且呈剂量依赖性。而[Tyr43]hPTH（43-68）和[Tyr52，Asp76]hPTH（52-84）则没有作用。利用一系列合成的hPTH肽覆盖激素分子的中心区域（残基25-47），我们可以进一步将这个假定的有丝分裂功能区域划分为氨基酸残基30和34之间的核心区域。PTH对[3H]胸苷结合的影响不能被福斯克林模拟，表明相应的信号不是由cAMP介导的。然而，它被EGTA抑制，并且在培养基中缺乏钙离子时不能被激发。因此，研究结果表明，PTH在分子中心部分存在一个迄今未被发现的功能域，该功能域以camp不依赖的方式对软骨细胞产生有丝分裂作用，但似乎涉及钙离子的信号转导。
The stimulation of DNA synthesis in primary cell cultures of chicken chondrocytes by parathyroid hormone was studied by assaying [3H]thymidine incorporation into DNA. Optimal assay conditions were determined by varying cell age, plating density, and incubation time. Under these conditions DNA synthesis was significantly stimulated by parathyroid hormone (PTH) and some of its fragments: cells treated with human (h)PTH(1–84), bovine (b)PTH(1–34) and [Nle8,18,Tyr34]bPTH(3–34)amide and hPTH(13–34) displayed 2.6-fold enhanced [3H]thymidine incorporation in a dose-dependent manner. The fragment hPTH(28–48) led to a similar stimulation, whereas [Tyr43]hPTH(43–68) and [Tyr52,Asp76]hPTH(52–84) had no effect. Using a series of synthetic hPTH peptides covering the central region of the hormone molecule (residues 25–47), we could delimitate further this putative mitogenic functional domain to a core region between amino acid residues 30 and 34. The effect of PTH on [3H]thymidine incorporation could not be mimicked by forskolin, indicating that the corresponding signal is not mediated by cAMP. It is, however, inhibited by EGTA and cannot be provoked in the absence of calcium ions in the medium. Therefore, the results presented indicate a hitherto unidentified functional domain of PTH in the central part of the molecule which exerts its mitogenic effect on chondrocytes in a cAMP-independent manner but seems to involve calcium ions for signal transduction.