Mazzuoli G F, D'Erasmo E, Scarda A, Minisola S, Mancini D, Aliberti L M
Calcif Tissue Int. 1979;29(3):185-91. doi: 10.1007/BF02408079.
Early effects of parathyroid hormone (PTH) deficiency were studied in 12 patients with primary hyperparathyroidism due to single parathyroid adenoma by following the precise time course of changes in plasma calcium (Ca) and immunoreactive parathyroid hormone (IPTH) after parathyroid surgery and by prelabeling 2 patients with radiocalcium (Ca*). Surgical removal of the adenoma was immediately followed by a sudden increase in plasma Ca which preceded the usual fall. The increase in plasma Ca commenced simultaneously with the fall in iPTH and was accompanied by a parallel increase in specific activity (sp. act.) of plasma Ca*. Specific activity continued to rise for 2 h in both prelabeled patients, whereas blood calcium was already falling thereafter reaching a markedly low removal rate constant as long as plasma Ca decreased. When plasma Ca began to rise, sp. act. resumed a descending course. Our findings indicate that the initial hypercalemia depends on PTH withdrawal and results from a rapid flux into general extracellular fluid (ECF) of calcium coming from a compartment with higher sp. act., contained within the miscible pool, immediately followed by a reduction in calcium transfer from bone. These results suggest that acute PTH deficiency determines an outflow of calcium from bone cells and support the theory that PTH initiates its action by modifying their intracellular calcium content.
通过追踪甲状旁腺手术后血浆钙（Ca）和免疫反应性甲状旁腺激素（IPTH）变化的精确时间进程，并对2例患者进行放射性钙（Ca*）预标记，研究了12例因单发甲状旁腺腺瘤导致原发性甲状旁腺功能亢进患者甲状旁腺激素（PTH）缺乏的早期影响。腺瘤手术切除后，血浆钙立即突然升高，且早于通常的下降。血浆钙的升高与iPTH的下降同时开始，并伴有血浆Ca*比活性（sp. act.）的平行升高。在两位预标记患者中，比活性持续上升2小时，而此后血钙已经开始下降，只要血浆钙降低，其去除率常数就会显著降低。当血浆钙开始上升时，比活性恢复下降趋势。我们的研究结果表明，最初的高钙血症取决于PTH的撤离，是由于来自混合池中具有较高比活性的钙池迅速流入一般细胞外液（ECF），随后骨钙转移减少所致。这些结果表明，急性PTH缺乏决定了骨细胞中钙的流出，并支持PTH通过改变其细胞内钙含量来启动其作用的理论。
