Yoshida H, Hamada N, Noh J, Ito K, Morii H
Second Department of Internal Medicine, Osaka City University Medical School, Japan.
Endocrinol Jpn. 1992 Feb;39(1):81-91. doi: 10.1507/endocrj1954.39.81.
To investigate serum levels of calcitonin gene-related peptide (CGRP), we developed a sensitive radioimmunoassay (RIA). RIA for CGRP in serum can present some problems: the serum may degradate the tracer during incubation and suppress the antigen-antibody reaction. We avoided these problems by using aprotinin and CGRP-free serum instead of a buffer for the standard curve. We detected serum CGRP in all 39 healthy subjects when CGRP-free serum was not used for the standard curve, but 34 of these subjects had serum CGRP levels below the detection limit (less than 80 pmol/l) when CGRP-free serum was used for the standard curve. We defined the normal range for serum CGRP as below 100.8 pmol/l, which was the maximum level found in the healthy subjects. We studied serum levels of this peptide in patients with thyroid diseases, because the thyroid may be one origin of circulating CGRP. Four of 10 patients with medullary thyroid carcinoma had elevated serum levels of CGRP. Seven of 24 patients with subacute thyroiditis had elevated serum levels of CGRP, but at least one year after clinical recovery, CGRP was undetectable in all. Seven of the 37 patients with hypothyroidism had elevated serum levels of CGRP. None of the patients with hyperthyroidism, adenomatous goiter, thyroid adenoma, or thyroid carcinoma had elevated serum CGRP levels. It is necessary to use a standard curve obtained by the addition of aprotinin and CGRP-free serum to the assay standards to measure serum CGRP levels. Some patients with subacute thyroiditis, hypothyroidism, or medullary thyroid carcinoma had elevated serum CGRP levels.
为了研究降钙素基因相关肽（CGRP）的血清水平，我们开发了一种灵敏的放射免疫分析方法（RIA）。血清中CGRP的RIA可能存在一些问题：血清在孵育过程中可能会降解示踪剂并抑制抗原抗体反应。我们通过使用抑肽酶和无CGRP血清代替标准曲线的缓冲液来避免这些问题。当标准曲线不使用无CGRP血清时，我们在所有39名健康受试者中均检测到了血清CGRP，但当标准曲线使用无CGRP血清时，其中34名受试者的血清CGRP水平低于检测限（低于80 pmol/L）。我们将血清CGRP的正常范围定义为低于100.8 pmol/L，这是健康受试者中发现的最高水平。我们研究了甲状腺疾病患者中这种肽的血清水平，因为甲状腺可能是循环CGRP的来源之一。10例甲状腺髓样癌患者中有4例血清CGRP水平升高。24例亚急性甲状腺炎患者中有7例血清CGRP水平升高，但在临床恢复至少一年后，所有患者的CGRP均无法检测到。37例甲状腺功能减退患者中有7例血清CGRP水平升高。甲亢、腺瘤性甲状腺肿、甲状腺腺瘤或甲状腺癌患者中均无血清CGRP水平升高。在检测血清CGRP水平时，有必要使用通过向测定标准品中添加抑肽酶和无CGRP血清获得的标准曲线。一些亚急性甲状腺炎、甲状腺功能减退或甲状腺髓样癌患者的血清CGRP水平升高。
