THYROXINE PROTEIN INTERACTIONS

甲状腺素蛋白相互作用

• 批准号: 3964783
• 负责人: J ROBBINS
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF DIABETES AND DIGESTIVE AND KIDNEY DISEASES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3964783
• 关键词: affinity chromatography; apolipoproteins; blood proteins; chemical stability; circular dichroism; dialysis; electrofocusing; electron spin resonance spectroscopy; fluorescence polarization; gel electrophoresis; high density lipoproteins; hormone inhibitor; human tissue; immunochemistry; low density lipoprotein; oligosaccharides; radioassay; radioimmunoassay; thyroid disorder; thyroid hormones; thyroxine; very low density lipoprotein

While TBG, prealbumin and albumin constitute the universally accepted major thyroid hormone binding system in human plasma, convincing evidence for similar binding to plasma lipoproteins is lacking. In a systematic study using Sepharose CL-6B chromatography to examine plasma from normal subjects and patients with genetic lipoprotein abnormalities, the interaction between thyroid hormone and the individual lipoprotein classes (VLDL, LDL and HDL) was unequivocally demonstrated. Binding of thyroxine was greater than that of triiodothyronine, and binding appeared to depend on the protein moieties of the ipoproteins. Whether this interaction, which accounts for less than 1-2% of thyroid hormone transport, plays any physiological role requires further study. Since serum TBG levels measured by an immunoradiometric assay (IRM, Corning kit) in patients with nonthyroid illness (NTI) are lower than those measured by radioimmunoassay (RIA), the effect of lipids known to be elevated in NTI, and various drugs, were tested for their ability to inhibit the binding of thyroxine to TBG. Unsaturated fatty acids and drugs such as furosemide, diclofenac and mefenamic acid were effective inhibitors. It was concluded that RIA is preferable to IRM for measuring TBG in NTI, and that TBG-IRM is a convenient and rapid method to test for thyroid hormone binding inhibitors.

而胆红素、前白蛋白和白蛋白是公认的主要成分 人血浆中的甲状腺激素结合系统，令人信服的证据 缺乏与血浆脂蛋白类似的结合。在系统的研究中 SepharoseCL-6B柱层析法检测正常人血浆 与遗传性脂蛋白异常患者的相互作用 甲状腺激素与个体脂蛋白类别(极低密度脂蛋白、低密度脂蛋白)之间的关系 和高密度脂蛋白)得到了明确的证明。甲状腺激素的结合力更强 比三碘甲腺原氨酸更强，结合似乎取决于 脂蛋白的蛋白质部分。无论这种互动， 占甲状腺激素转运的不到1%-2%， 生理作用有待进一步研究。 由于血清总胆红素水平是通过免疫放射测定法(IRM，Corning 在非甲状腺疾病(NTI)患者中， 通过放射免疫分析(RIA)测量，已知的血脂的影响是 在NTI和各种药物中升高，测试它们的能力 抑制甲状腺激素与总胆红素的结合。不饱和脂肪酸与药物 如速尿、双氯芬酸、甲芬酸等有效 抑制剂。结论：RIA法比IRM法更适合于测量 TBG-IRM是一种方便和快速测试方法 甲状腺激素结合抑制剂。