Lothrop C D, Oliver J W
Am J Vet Res. 1984 Nov;45(11):2304-9.
A comparison of cortisol concentrations, determined by high-performance liquid chromatography (HPLC) and radioimmunoassay, was made in healthy, mixed-breed dogs and in dogs with clinical signs of Cushing's syndrome. Absolute concentration of cortisol was less in resting, dexamethasone-suppressed, and ACTH-stimulated plasma samples, when measured by HPLC relative to cortisol concentrations determined by radioimmunoassay. Diagnosis of Cushing's syndrome could be made using either method. Plasma concentrations of cortisone and corticosterone were determined by HPLC. Cortisone and corticosterone concentrations alone were not diagnostic of Cushing's syndrome; but when used in conjunction with cortisol determinations, they provided additional criteria for laboratory confirmation of the clinical diagnosis of Cushing's syndrome. The clearance of exogenous dexamethasone used in the dexamethasone-suppression test was examined in the normal and cushingoid dogs. Plasma concentrations of exogenous dexamethasone were constant during the 3-hour test in the normal dogs. However, in 75% of the dogs with Cushing's syndrome, exogenous dexamethasone was cleared completely in the 3-hour test. Thus, dexamethasone clearance rates were excessively fast in most dogs with Cushing's syndrome.
采用高效液相色谱法（HPLC）和放射免疫分析法对健康杂种犬和患有库欣综合征临床症状的犬的皮质醇浓度进行了比较。相对于放射免疫分析法测定的皮质醇浓度，用HPLC法测量时，静息、地塞米松抑制和促肾上腺皮质激素刺激的血浆样本中皮质醇的绝对浓度较低。使用任何一种方法都可以诊断库欣综合征。通过HPLC法测定了可的松和皮质酮的血浆浓度。单独的可的松和皮质酮浓度不能诊断库欣综合征；但与皮质醇测定结合使用时，它们为实验室确认库欣综合征的临床诊断提供了额外的标准。在正常犬和患库欣综合征的犬中检测了地塞米松抑制试验中使用的外源性地塞米松的清除情况。在正常犬的3小时试验期间，外源性地塞米松的血浆浓度保持恒定。然而，在75%患有库欣综合征的犬中，外源性地塞米松在3小时试验中被完全清除。因此，大多数患有库欣综合征的犬的地塞米松清除率过快。
