Au W Y, Poland A P, Stern P H, Raisz L G
J Clin Invest. 1970 Sep;49(9):1639-46. doi: 10.1172/JCI106381.
Rat parathyroid glands maintained in organ culture secrete biologically active parathyroid hormone (PTH) and synthesize and secrete labeled proteins from (3)H- or (14)C-labeled amino acids added to the medium. The amounts of biological activity and labeled protein in the medium are both inversely proportional to the calcium concentration. Some of the labeled low molecular weight protein was identified as PTH which had been synthesized and secreted in culture by preliminary isolation on Sephadex G-100 columns and further purification using an antibody to bovine PTH which cross-reacted with rat PTH. The cross-reacting antibody inhibited the biological effects of rat PTH and caused hypocalcemia in intact rats. The antibody bound some of the labeled low molecular weight protein of the medium at neutral pH so that it migrated as a large molecular weight complex on Sephadex. Biologically active, labeled PTH was recovered by dissociation of this complex in acid and rechromatography.
维持在器官培养中的大鼠甲状旁腺分泌具有生物活性的甲状旁腺激素（PTH），并从添加到培养基中的³H或¹⁴C标记氨基酸合成并分泌标记蛋白。培养基中生物活性和标记蛋白的量均与钙浓度成反比。通过在Sephadex G - 100柱上初步分离并使用与大鼠PTH发生交叉反应的抗牛PTH抗体进一步纯化，确定部分标记的低分子量蛋白为在培养中合成和分泌的PTH。该交叉反应抗体抑制大鼠PTH的生物学效应，并在完整大鼠中引起低钙血症。该抗体在中性pH下结合培养基中一些标记的低分子量蛋白，使其在Sephadex上作为大分子复合物迁移。通过在酸性条件下解离该复合物并重新色谱分离回收具有生物活性的标记PTH。
