PHYSIOLOGICAL ROLE OF THYROXINE BINDING PROTEINS

甲状腺素结合蛋白的生理作用

• 批准号: 3234571
• 负责人: PHILIP REED LARSEN
• 金额: $ 20.62万
• 依托单位: BRIGHAM AND WOMEN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 1985
• 资助国家: 美国
• 起止时间: 1985-01-01 至 1992-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3234571
• 关键词: adipose tissue; calcium; catecholamines; chromatography; enzyme biosynthesis; enzyme mechanism; gel electrophoresis; gene expression; genetic library; glucagon; hamsters; hormone metabolism; hormone regulation /control mechanism; hyperthyroidism; hypopituitarism; hypothyroidism; insulin; ion exchange chromatography; laboratory mouse; laboratory rabbit; laboratory rat; monoclonal antibody; nucleic acid sequence; pituitary neoplasms; protein biosynthesis; protein kinase C; radioassay; secretion; thyroid function; thyroid hormone binding protein; thyroid hormones; thyrotropin releasing hormone; tissue /cell culture; triiodothyronine

A major long-term objective of this proposal is to evaluate the regulation of the Type II iodothyronine 5'-deiodinase in brown adipose tissue, pituitary, and cerebral cortex. The enzymatic mechanism of T4 to T3 conversion will be examined by isolating the enzyme and the regulation of its activation elucidated by studying intracellular processes leading to alterations in enzyme activity. These may be due to changes in the rate of enzyme synthesis or to activation of existing enzyme or co-factors. The effects of catecholamines, insulin, glucagon, and thyroid hormone on 5'-deiodinase will be evaluated and the mechanisms elucidated in brown adipocytes from rat or hamster. In addition, we will examine the effects of hypo- and hyperthyroidism (T3 induced) and hypopituitarism on the response of their cells to those hormones. The chronology of the changes in enzyme responsiveness with these manipulations will be examined and correlated with changes in the intermediary metabolism of the brown fat cell. Immunization of rabbits and mice will be performed to produce polyclonal or monoclonal antibodies to be used as enzyme probes. Isolation of the enzyme for immunizations will be done by ion exchange and hydrophobic interaction chromatography. These products will also be used to screen expression libraries of cDNA prepared from the brown adipose tissue of rats which have been shown to have high rates of enzyme synthesis. The amino acid sequence of the enzyme will be determined from the cDNA sequence. In other studies, the role of thyroid hormone in regulation of TSH release from isolated pituitary cells will be investigated by techniques employing somatic cell fusion of thyrotroph enriched rat pituitaries with pituitary tumor cells. Permanent lines developed from such fusions have been found to replicate and continuously secrete TSH giving them a significant advantage over either primary cultures or the mouse thyrotroph tumors which do not replicate. The effects of TRH, thyroid hormone, and other secretagogues on TSH secretion from these cells will be evaluated to determine the mechanism for the thyroid hormone inhibition of TSH release from these cells. This research is relevant to the treatment of hypothyroidism (especially in newborns), the problem of obesity, survival during cold stress and the design and propoer interpretation of tests of thyroid function.

该提议的主要长期目标是评估 棕色II型碘甲氧氨酸5'-二二肽酶的调节 脂肪组织，垂体和脑皮质。 酶促 T4至T3转换的机理将通过隔离检查 酶及其激活的调节阐明了 研究导致酶改变的细胞内过程 活动。 这些可能是由于酶速率的变化所致 合成或激活现有酶或副因素。 这 儿茶酚胺，胰岛素，胰高血糖素和甲状​​腺激素的影响 将评估5'-二碘酶，并阐明了机制 在大鼠或仓鼠的棕色脂肪细胞中。 此外，我们将 检查甲状腺功能亢进和甲状腺功能亢进的作用（T3诱导） 以及对细胞对那些细胞反应的反应性降低性 激素。 酶变化的年代学 将检查这些操纵的响应能力，并 与中介代谢的变化相关 棕色脂肪细胞。 兔子和小鼠的免疫 进行多克隆或单克隆抗体的进行 用作酶探针。 分离酶 免疫将通过离子交换和疏水进行 相互作用色谱。 这些产品也将用于 由棕色制备的cDNA的屏幕表达式文库 大鼠的脂肪组织已证明具有很高的速率 酶合成。 酶的氨基酸序列将是 由cDNA序列确定。 在其他研究中， 甲状腺激素从分离的TSH释放调节中 垂体细胞将通过采用技术研究 与甲状腺营养的体细胞融合富含大鼠垂体 垂体肿瘤细胞。 永久性线从这种情况下发展 已经发现融合可以复制并连续分泌TSH 给他们比任何一级文化的重要优势 或不复制的小鼠甲状腺营养肿瘤。 这 TRH，甲状腺激素和其他促分子对TSH的影响 将评估这些细胞的分泌，以确定 甲状腺激素抑制TSH释放的机制 从这些细胞中。 这项研究与治疗 甲状腺功能减退症（尤其是在新生儿），肥胖问题， 在冷应力和设计和提议者期间的生存 甲状腺功能测试的解释。