Binding of thyrotropin to lentil lectin is unchanged by thyrotropin-releasing hormone administration in three patients with thyrotropin-producing pituitary adenomas.
Binding of thyrotropin to lentil lectin is unchanged by thyrotropin-releasing hormone administration in three patients with thyrotropin-producing pituitary adenomas.
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在三名产生促甲状腺素的垂体腺瘤患者中，给予促甲状腺素释放激素后，促甲状腺素与扁豆凝集素的结合没有改变。
DOI：
10.1080/07435809209026675
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发表时间：
1992
影响因子：
2.1
通讯作者：
Kane,J
中科院分区：
文献类型：
--
作者：
Magner,JA;Kane,J
糖蛋白对扁豆凝集素的亲和力增加，当聚焦残基在其天冬酰胺连接的低聚糖的“核心区域”与n -乙酰氨基葡萄糖结合时。在3例促甲状腺素（TSH）产生的垂体肿瘤患者中，与扁豆结合的血清TSH异构体比例（70.8%±15%）高于正常人（32.5±8%）。与正常受试者不同，肿瘤患者急性给予TSH释放激素（TRH）后，循环中TSH的浓度没有升高，与基础TSH相比，TSH与扁豆的结合也没有增加。1例肿瘤患者服用甲氧氯普胺后，TSH与扁豆的结合降低，但服用甲氧氯普胺或左旋多巴后，TSH与扁豆的结合基本保持不变。我们的结论是，人类促甲状腺肿瘤组织，不像正常的促甲状腺，在药物刺激后通常不能释放更多的高度集中的TSH亚型，这可能是因为肿瘤组织不易被内分泌刺激调节，或者因为TSH已经相对高度集中。
Glycoproteins have increased affinity for lentil lectin when fucose residues are bound to N-acetylglucosamine in the “core region” of their asparagine-linked oligosaccharides. In three patients with thyrotropin (TSH)-producing pituitary tumors, the proportion of serum TSH isoforms that bound to lentil (70.8% ± 15%) was higher than that seen for TSH from normal persons (32.5 ± 8%). Unlike normal subjects, the concentration of TSH circulating in the tumor patients after acute administration of TSH-releasing hormone (TRH) did not rise, and the TSH did not exhibit increased binding to lentil compared to basal TSH. The TSH binding to lentil in one tumor patient decreased after metoclopramide, but TSH binding to lentil generally remained unchanged after metoclopramide or L-dopa administration. We conclude that human thyrotropic tumor tissue, unlike normal thyrotrophs, generally fails to release more highly fucosylated isoforms of TSH after pharmacologic stimulation, perhaps because the tumor tissue is less readily modulated by endocrine stimuli, or because the TSH is already relatively highly fucosylated.