Mizobuchi M, Kunishige M, Kubo K, Komatsu M, Bando H, Saito S
First Department of Internal Medicine, School of Medicine, Tokushima University.
Intern Med. 1994 Aug;33(8):501-4. doi: 10.2169/internalmedicine.33.501.
A 76-year-old man with small cell lung cancer associated with the syndrome of inappropriate secretion of ADH (SIADH) visited our hospital. The serum Na level was normal on the first visit, but 2 weeks later it decreased to 114 mEq/L with an extremely high plasma vasopressin (VP) level of 1520 pg/ml. Serum Na was normalized after the reduction of the tumor size by chemotherapy, but the plasma VP level remained between 150 to 600 pg/ml. On gel filtration of plasma VP two peaks of immunoreactive VP were eluted at the positions of a larger molecule than authentic VP and authentic VP, and VP in urine gave only one peak compared to that of authentic VP. The dilution curve of plasma VP was almost parallel and that of urine was completely parallel to the standard curve. These findings suggest that a larger VP with low physiological activity was predominantly secreted in the present patient and manifested relatively mild symptoms despite the extremely high plasma VP level.
一名76岁患有小细胞肺癌并伴有抗利尿激素分泌不当综合征（SIADH）的男性患者前来我院就诊。初诊时血清钠水平正常，但2周后降至114 mEq/L，血浆血管加压素（VP）水平极高，达1520 pg/ml。化疗使肿瘤缩小后血清钠恢复正常，但血浆VP水平仍维持在150至600 pg/ml之间。对血浆VP进行凝胶过滤时，免疫反应性VP出现两个峰，一个位于比天然VP分子量大的位置，另一个与天然VP位置相同，而尿中的VP与天然VP相比仅出现一个峰。血浆VP的稀释曲线几乎平行，尿的稀释曲线与标准曲线完全平行。这些发现表明，该患者主要分泌生理活性较低的大分子VP，尽管血浆VP水平极高，但症状相对较轻。
