Mizunashi K, Furukawa Y, Abe K, Yoshinaga K
Second Department of Internal Medicine, Tuhoku University School of Medicine, Sendai, Japan.
Calcif Tissue Int. 1993 Dec;53(6):378-83.
We studied the relationship between serum calcium (Ca) and parathyroid hormone (PTH) in patients with idiopathic hypoparathyroidism (IHP) to investigate the diversity of the degree of parathyroid insufficiency and a regulation of PTH secretion by Ca in IHP. Serum intact PTH concentrations ranged from < 1.0 to 10.3 pg/ml in 20 patients with IHP and were above the detection limit in 18 (90%) patients. Serum total Ca levels in IHP were positively correlated with serum intact PTH (r = 0.824, P < 0.001), in contrast with a negative correlation between serum intact PTH and Ca in 91 normal subjects (r = -0.378, P < 0.001) and abnormally high serum intact PTH values against hypocalcemia in five patients with pseudohypoparathyroidism. In three patients with IHP, serum intact PTH decreased in response to treatment with active vitamin D3 which increased serum Ca and 1,25(OH)2D. An inverse sigmoidal relationship between serum ionized Ca and intact PTH was demonstrated in a patient with IHP before treatment [IHP(-)] and three patients with IHP treated with active vitamin D3[IHP(+)]. Peak serum intact PTH values were reduced in IHP(-) and IHP(+). Baseline serum intact PTH was 77.0% of the maximal level in IHP(-), 51.7-72.1% in IHP(+), and 31.1-42.3% in five normal subjects. The degree of parathyroid dysfunction in IHP differs from one patient to another and serum Ca levels are thought to be determined by circulating PTH levels. Although PTH secretory reserve is diminished, PTH secretion is negatively regulated by Ca and is stimulated at baseline in patients with IHP before and during the treatment with active vitamin D3.
我们研究了特发性甲状旁腺功能减退症（IHP）患者血清钙（Ca）与甲状旁腺激素（PTH）之间的关系，以探讨甲状旁腺功能不全程度的多样性以及IHP中Ca对PTH分泌的调节作用。20例IHP患者血清完整PTH浓度范围为<1.0至10.3 pg/ml，18例（90%）患者高于检测限。IHP患者血清总钙水平与血清完整PTH呈正相关（r = 0.824，P < 0.001），相比之下，91例正常受试者血清完整PTH与Ca呈负相关（r = -0.378，P < 0.001），且5例假性甲状旁腺功能减退症患者存在血钙过低时血清完整PTH值异常升高的情况。在3例IHP患者中，活性维生素D3治疗使血清Ca和1,25(OH)2D升高，血清完整PTH降低。1例未治疗的IHP患者[IHP(-)]和3例接受活性维生素D3治疗的IHP患者[IHP(+)]中，血清离子钙与完整PTH呈反S形关系。IHP(-)和IHP(+)患者血清完整PTH峰值降低。IHP(-)患者基线血清完整PTH为最高水平的77.0%，IHP(+)患者为51.7 - 72.1%，5例正常受试者为31.1 - 42.3%。IHP患者甲状旁腺功能障碍程度因人而异，血清Ca水平被认为由循环PTH水平决定。尽管PTH分泌储备减少，但IHP患者在活性维生素D3治疗前及治疗期间，PTH分泌受Ca负调节且在基线时受到刺激。
