Johnson E O, Vlachoyiannopoulos P G, Skopouli F N, Tzioufas A G, Moutsopoulos H M
Department of Anatomy, University of Ioannina, School of Medicine, Greece.
J Rheumatol. 1998 Aug;25(8):1508-14.
To examine the functional integrity of the hypothalamic-pituitary-adrenal (HPA) and thyroid axes in Sjögren's syndrome (SS) via the assessment of basal and stimulated adrenocorticotropin (ACTH), cortisol, thyroid stimulating hormone (TSH), and prolactin levels.
Pituitary function of the HPA axis was assessed by determining the basal plasma levels of ACTH in the late afternoon, as well as the ACTH released to ovine corticotropin releasing hormone (oCRH) stimulation; adrenal function was assessed by measuring plasma cortisol levels in the late afternoon at baseline and after release of the endogenous ACTH during oCRH stimulation. Basal and thyrotropin releasing hormone (TRH) stimulated levels of TSH and prolactin were also assessed. Healthy volunteers were used as controls.
Patients with SS, compared to controls, were characterized by significantly lower ACTH levels (pg/ml), (5.1 +/- 0.5 vs 11.4 +/- 1.5, respectively; p < 0.05) and cortisol levels (microg/ml), (2.4 +/- 0.6 vs 5.9 +/- 1.2, respectively; p < 0.05). Furthermore, a blunted pituitary and adrenal response to oCRH compared to controls was observed: peak plasma ACTH and cortisol levels for patients with SS were 46.2 +/- 5.4 pg/ml and 15.7 +/- 1.6 microg/ml, respectively, and for controls 61.5 +/- 3.8 and 19.6 +/- 0.7, respectively (p < 0.05). Basal TSH levels were significantly elevated in patients (1.3 +/- 0.3 microIU/ml vs 0.9 +/- 0.05 microIU/ml; p < 0.05).
The above findings indicate hypoactivity of the HPA axis in patients with SS. Further studies are needed to definitively identify the locus of the defects and assess the significance of the pattern of the perturbations to the pathogenesis and expression of SS.
通过评估基础及刺激后的促肾上腺皮质激素（ACTH）、皮质醇、促甲状腺激素（TSH）和催乳素水平，检测干燥综合征（SS）患者下丘脑-垂体-肾上腺（HPA）轴和甲状腺轴的功能完整性。
通过测定下午晚些时候的基础血浆ACTH水平以及对羊促肾上腺皮质激素释放激素（oCRH）刺激的反应来评估HPA轴的垂体功能；通过测量下午晚些时候的基础血浆皮质醇水平以及oCRH刺激期间内源性ACTH释放后的皮质醇水平来评估肾上腺功能。还评估了基础及促甲状腺激素释放激素（TRH）刺激后的TSH和催乳素水平。以健康志愿者作为对照。
与对照组相比，SS患者的ACTH水平（pg/ml）显著降低（分别为5.1±0.5和11.4±1.5；p<0.05），皮质醇水平（μg/ml）也显著降低（分别为2.4±0.6和5.9±1.2；p<0.05）。此外，与对照组相比，观察到垂体和肾上腺对oCRH的反应减弱：SS患者的血浆ACTH和皮质醇峰值水平分别为46.2±5.4 pg/ml和15.7±1.6 μg/ml，而对照组分别为61.5±3.8和19.6±0.7（p<0.05）。患者的基础TSH水平显著升高（1.3±0.3 μIU/ml对0.9±0.05 μIU/ml；p<0.05）。
上述发现表明SS患者HPA轴功能减退。需要进一步研究以明确缺陷的部位，并评估这些扰动模式对SS发病机制和表现的意义。
