钙对动力缺失型肾性骨营养不良和继发性甲状旁腺功能亢进中甲状旁腺激素释放的抑制作用。

Suppressive effect of calcium on parathyroid hormone release in adynamic renal osteodystrophy and secondary hyperparathyroidism.

作者信息

Goodman W G, Veldhuis J D, Belin T R, Juppner H, Salusky I B

机构信息

Department of Medicine, UCLA School of Medicine, USA.

出版信息

Kidney Int. 1997 May;51(5):1590-5. doi: 10.1038/ki.1997.218.

DOI:10.1038/ki.1997.218

PMID:9150477

Abstract

Serum parathyroid hormone (PTH) levels are markedly lower in patients with the adynamic lesion (AD) of renal osteodystrophy than in those with secondary hyperparathyroidism (2 degrees HPT), but serum PTH values are often moderately elevated in AD when compared to subjects with normal renal and parathyroid gland function (NL). To study the inhibitory effect of calcium on PTH release in AD and in 2 degrees HPT, the response to two-hour intravenous calcium infusions was examined in 6 patients with AD, in 31 patients with 2 degrees HPT and in 20 NL. Basal serum PTH levels were 88 +/- 51, 536 +/- 395, and 26 +/- 6 pg/ml, respectively, in AD, 2 degrees HPT and NL, whereas basal ionized calcium levels did not differ. When expressed as a percentage of pre-infusion values, PTH levels at the end of two-hour calcium infusions were higher both in AD (23.2 +/- 5.6%) and in 2 degrees HPT (27.8 +/- 12.3%) than in NL, (11.9 +/- 5.8%, P < 0.001). Both the amplitude of suppression (%) and the rate of decline (min-1) in serum PTH were less in AD and 2 degrees HPT than in NL, P < 0.05 for each parameter; corresponding values for each group, with 95% confidence intervals, were 77% (73 to 82) and 0.039 min-1 (0.030 to 0.048) in AD, 72% (68 to 76) and 0.031 min-1 (0.025 to 0.036) in 2 degrees HPT and 87% (84 to 89) and 0.070 min-1 (0.058 to 0.089) in NL. Neither variable differed between AD and 2 degrees HPT. Basal and nadir serum PTH levels were highly correlated: r = 0.95 and P < 0.05 in AD; r = 0.90 and P < 0.01 in 2 degrees HPT; r = 0.75 and P < 0.01 in NL. The slope of this relationship was less, however, both in AD and in 2 degrees HPT than in NL, P < 0.05 by analysis of co-variance. Thus, serum PTH levels fell below 20% of pre-infusion values in fewer subjects with AD (1 of 6) or 2 degrees HPT (9 of 31) than in NL (17 of 20) (chi 2 = 17.81, P < 0.005). The results indicate that the inhibitory effect of calcium on PTH release in vivo does not differ in AD and 2 degrees HPT despite marked differences in basal serum PTH levels. Variations in functional parathyroid gland mass rather than disturbances in calcium-sensing by the parathyroids probably account not only for the lower basal serum PTH levels in patients with AD compared to those with 2 degrees HPT, but also for the moderately elevated serum PTH values commonly seen in patients with AD.

摘要

肾性骨营养不良的无动力性骨损害（AD）患者的血清甲状旁腺激素（PTH）水平明显低于继发性甲状旁腺功能亢进（2度HPT）患者，但与肾功能和甲状旁腺功能正常（NL）的受试者相比，AD患者的血清PTH值通常中度升高。为了研究钙对AD和2度HPT患者PTH释放的抑制作用，对6例AD患者、31例2度HPT患者和20例NL受试者进行了两小时静脉输注钙的反应研究。AD、2度HPT和NL患者的基础血清PTH水平分别为88±51、536±395和26±6 pg/ml，而基础离子钙水平无差异。以输注前值的百分比表示，两小时钙输注结束时AD组（23.2±5.6%）和2度HPT组（27.8±12.3%）的PTH水平均高于NL组（11.9±5.8%，P<0.001）。AD组和2度HPT组血清PTH的抑制幅度（%）和下降速率（min-1）均低于NL组，各参数P<0.05；每组相应值及其95%置信区间为：AD组77%（73至82）和0.039 min-1（0.030至0.048），2度HPT组72%（68至76）和0.031 min-1（0.025至0.036），NL组87%（84至89）和0.070 min-1（0.058至0.089）。AD组和2度HPT组之间这两个变量均无差异。基础血清PTH水平与最低血清PTH水平高度相关：AD组r=0.95，P<0.05；2度HPT组r=0.90，P<0.01；NL组r=0.75，P<0.01。然而，通过协方差分析，AD组和2度HPT组这种关系的斜率均低于NL组，P<0.05。因此，血清PTH水平降至输注前值20%以下的AD患者（6例中的1例）或2度HPT患者（31例中的9例）少于NL患者（20例中的17例）（χ2=17.81，P<0.005）。结果表明，尽管基础血清PTH水平存在显著差异，但钙对AD和2度HPT患者体内PTH释放的抑制作用并无差异。功能性甲状旁腺质量的变化而非甲状旁腺对钙的感知障碍可能不仅是AD患者基础血清PTH水平低于2度HPT患者的原因，也是AD患者常见的血清PTH值中度升高的原因。