Javadi Shahram, Galac Sara, Boer Peter, Robben Joris H, Teske Erik, Kooistra Hans S
Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, The Netherlands.
J Vet Intern Med. 2006 May-Jun;20(3):556-61. doi: 10.1892/0891-6640(2006)20[556:aachri]2.0.co;2.
In dogs with primary hypoadrenocorticism, hypocortisolism and hypoaldosteronism usually are present, but these deficiencies also may occur in isolated forms. The diagnosis is commonly made by measuring plasma cortisol concentration before and after stimulation with ACTH, thereby ignoring aldosterone. In search of an alternative approach that would include assessment of glucocorticoid and mineralocorticoid production, 2 pairs of endocrine variables were measured: (1) plasma concentration of cortisol and ACTH, and (2) plasma aldosterone concentration and plasma renin activity. In addition, the cortisol-to-ACTH ratio (CAR) and the aldosterone-to-renin ratio (ARR) were calculated. Reference intervals were established in a population of 60 healthy dogs. In these dogs, CAR ranged from 1.1 to 26.1 and ARR ranged from 0.1 to 1.5. The variables were compared with those of 22 dogs with spontaneous primary hypoadrenocorticism. Plasma concentration of cortisol and ACTH in both groups of dogs overlapped, whereas CAR did not. Similarly, plasma aldosterone concentration and plasma renin activity overlapped, whereas ARR did not. These observations indicate that measurement of these endogenous variables (in one blood sample) allows the specific diagnoses of primary hypocortisolism and primary hypoaldosteronism.
在患有原发性肾上腺皮质功能减退症的犬中，通常存在皮质醇减少症和醛固酮减少症，但这些缺乏症也可能以孤立的形式出现。诊断通常是通过测量促肾上腺皮质激素（ACTH）刺激前后的血浆皮质醇浓度来进行的，从而忽略了醛固酮。为了寻找一种能够评估糖皮质激素和盐皮质激素产生情况的替代方法，测量了2对内分泌变量：（1）皮质醇和ACTH的血浆浓度，以及（2）血浆醛固酮浓度和血浆肾素活性。此外，还计算了皮质醇与ACTH的比值（CAR）和醛固酮与肾素的比值（ARR）。在60只健康犬中建立了参考区间。在这些犬中，CAR范围为1.1至26.1，ARR范围为0.1至1.5。将这些变量与22只患有自发性原发性肾上腺皮质功能减退症的犬的变量进行了比较。两组犬的皮质醇和ACTH血浆浓度有重叠，但CAR没有。同样，血浆醛固酮浓度和血浆肾素活性有重叠，但ARR没有。这些观察结果表明，测量这些内源性变量（在一份血液样本中）可以对原发性皮质醇减少症和原发性醛固酮减少症进行特异性诊断。
