Bonadonna Stefania, Burattin Anna, Nuzzo Monica, Bugari Giovanna, Rosei Enrico Agabiti, Valle Domenico, Iori Nicoletta, Bilezikian John P, Veldhuis Johannes D, Giustina Andrea
Department of Medical Sciences, University of Brescia, Brescia, Italy.
Eur J Endocrinol. 2005 Feb;152(2):199-205. doi: 10.1530/eje.1.01841.
Spontaneous parathyroid hormone (PTH) secretory dynamics include tonic and pulsatile components. It is not known how glucocorticoids might alter these secretory dynamics.
The aim of our study was to evaluate spontaneous fluctuations in serum PTH levels in six adult male patients (aged 31-64 years) receiving chronic (>6 months) therapy with glucocorticoids (daily dosage >7.5 mg of prednisone or dose equivalent of other corticosteroid) as compared with a control group of 10 age- and sex-matched normal subjects.
Peripheral venous blood sampling was performed every 3 min for 6 h from 0900 to 1500 h. Plasma PTH release profiles were subjected to deconvolution analysis, a method that resolves measured hormone concentrations into secretion and clearance components, and to an approximate entropy (ApEn) estimate, that in turn provides an integrated measure of the serial regularity or orderliness of the release process.
In the glucocorticoid-treated group, the PTH tonic secretory rate was reduced (4.3+/-0.74 vs 8.8+/-1.4 pg/ml per min in controls, P = 0.017). There was, however, an increase in the fractional pulsatile PTH secretion (42+/-8.2 vs 18.3+/-3.9 pg/ml per min, P = 0.006) in glucocorticoid-treated vs normal subjects. Mean overall PTH concentration, as well as mean integrated area, was similar among normal and glucocorticoid-treated subjects.
These results demonstrate, for the first time, that chronic glucocorticoid treatment induces a redistribution of spontaneous PTH secretory dynamics by reducing the amount released in tonic fashion and increasing the amount released as pulses.
甲状旁腺激素（PTH）的自发性分泌动力学包括持续性和脉冲性成分。目前尚不清楚糖皮质激素如何改变这些分泌动力学。
我们研究的目的是评估6例接受糖皮质激素慢性（>6个月）治疗（每日剂量>7.5 mg泼尼松或其他皮质类固醇等效剂量）的成年男性患者（年龄31 - 64岁）血清PTH水平的自发性波动，并与10名年龄和性别匹配的正常受试者组成的对照组进行比较。
在09:00至15:00期间，每3分钟采集一次外周静脉血样，共采集6小时。血浆PTH释放曲线进行去卷积分析，该方法将测得的激素浓度分解为分泌和清除成分，并进行近似熵（ApEn）估计，进而提供释放过程序列规律性或有序性的综合测量。
在糖皮质激素治疗组中，PTH的持续性分泌率降低（4.3±0.74 vs对照组8.8±1.4 pg/ml每分钟，P = 0.017）。然而，与正常受试者相比，糖皮质激素治疗组中PTH脉冲性分泌分数增加（42±8.2 vs 18.3±3.9 pg/ml每分钟，P = 0.006）。正常受试者和糖皮质激素治疗组的平均总体PTH浓度以及平均积分面积相似。
这些结果首次表明，慢性糖皮质激素治疗通过减少持续性释放量和增加脉冲释放量，诱导了自发性PTH分泌动力学的重新分布。
