Levine M A, Dempsey M A, Helman L J, Ahn T G
Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205.
J Clin Endocrinol Metab. 1990 Jun;70(6):1668-73. doi: 10.1210/jcem-70-6-1668.
Chromogranin-A (CgA), also termed secretory protein-I, is an acidic glycoprotein that is synthesized and secreted by cells of the diffuse endocrine and neuroendocrine system. Several previous studies had suggested that plasma levels of CgA were elevated in patients with primary hyperparathyroidism. In the present study we sought to examine expression of the CgA gene in human parathyroid tissue from patients with primary hyperparathyroidism. We characterized the mRNAs coding for CgA and beta-actin in parathyroid tissue fragments obtained from 12 patients with parathyroid adenomas, 11 patients with familial multiple endocrine neoplasia type I (FMEN I) with parathyroid hyperplasia, and 11 normal subjects. The mRNAs were detected and analyzed by dot and Northern blot hybridization using cDNA probes. CgA mRNA transcripts of 2.1 kilobases were detected in normal and pathological parathyroids. Similarly, beta-actin mRNA species of 2.1 kilobases was present in all tissues. The relative level of parathyroid tissue CgA mRNA, calculated as the CgA/beta-actin mRNA ratio, was 73 +/- 18 in parathyroid adenoma, 73 +/- 20 in FMEN I, and 100 +/- 9 in controls (mean +/- SE; expressed as a percentage of the control reference group value). There were no significant differences among the steady state levels of CgA mRNA levels in these three groups (F = 0.98; P = 0.39). These results demonstrate that expression of CgA mRNA is qualitatively and quantitatively normal in parathyroid tumors from patients with FMEN I and parathyroid adenoma.
嗜铬粒蛋白A（CgA），也称为分泌蛋白I，是一种酸性糖蛋白，由弥散内分泌和神经内分泌系统的细胞合成并分泌。先前的几项研究表明，原发性甲状旁腺功能亢进患者的血浆CgA水平升高。在本研究中，我们试图检测原发性甲状旁腺功能亢进患者甲状旁腺组织中CgA基因的表达。我们对从12例甲状旁腺腺瘤患者、11例患有甲状旁腺增生的I型家族性多发性内分泌肿瘤（FMEN I）患者以及11名正常受试者获取的甲状旁腺组织片段中编码CgA和β-肌动蛋白的mRNA进行了表征。使用cDNA探针通过斑点杂交和Northern印迹杂交检测并分析mRNA。在正常和病变的甲状旁腺中均检测到2.1千碱基的CgA mRNA转录本。同样，所有组织中均存在2.1千碱基的β-肌动蛋白mRNA种类。以CgA/β-肌动蛋白mRNA比值计算的甲状旁腺组织CgA mRNA相对水平，在甲状旁腺腺瘤中为73±18，在FMEN I中为73±20，在对照组中为100±9（平均值±标准误；表示为对照参考组值的百分比）。这三组中CgA mRNA水平的稳态水平之间无显著差异（F = 0.98；P = 0.39）。这些结果表明，FMEN I患者和甲状旁腺腺瘤患者甲状旁腺肿瘤中CgA mRNA的表达在质量和数量上均正常。
