Duthie S M, Taylor P L, Anderson L, Cook J, Eidne K A
MRC Reproductive Biology Unit, Centre for Reproductive Biology, Edinburgh, UK.
Mol Cell Endocrinol. 1993 Sep;95(1-2):R11-5. doi: 10.1016/0303-7207(93)90043-j.
Thyrotrophin-releasing hormone (TRH) is a hypothalamic tripeptide known to act via its receptor in the anterior pituitary gland to stimulate the release of thyrotrophin (TSH) from thyrotrophs and prolactin (PRL) from lactotrophs. It is also thought to act as a neurotransmitter/neuromodulator in the central and peripheral nervous systems. We have isolated a cDNA encoding the human pituitary TRH receptor (TRH-R) protein with a predicted amino acid sequence of 398 amino acids. Comparison of the amino acid sequences of the human TRH-R with the previously published rodent TRH-Rs showed that it is similar to both the rat and mouse TRH-Rs, except that each species has variant amino acids at the carboxy (COOH) terminus. The human TRH-R belongs to the family of seven transmembrane domain, G-protein-coupled receptors, and it is believed that the COOH terminal region of this family of receptors may play an important role in receptor downregulation/internalisation, and possibly G-protein coupling. COS-1 cells expressing the human TRH-R showed high affinity receptor binding. Stimulation of these cells with TRH produced a typical phosphoinositide response and mobilisation of intracellular calcium [Ca2+]i.
促甲状腺激素释放激素（TRH）是一种下丘脑三肽，已知它通过其在前脑垂体中的受体发挥作用，刺激促甲状腺细胞释放促甲状腺激素（TSH）以及催乳细胞释放催乳素（PRL）。它也被认为在中枢和外周神经系统中作为神经递质/神经调节剂发挥作用。我们已经分离出一种编码人垂体TRH受体（TRH-R）蛋白的cDNA，其预测的氨基酸序列为398个氨基酸。将人TRH-R的氨基酸序列与先前发表的啮齿动物TRH-Rs进行比较，结果表明它与大鼠和小鼠的TRH-Rs均相似，只是每个物种在羧基（COOH）末端具有变异氨基酸。人TRH-R属于七跨膜结构域、G蛋白偶联受体家族，据信该受体家族的COOH末端区域可能在受体下调/内化以及可能的G蛋白偶联中发挥重要作用。表达人TRH-R的COS-1细胞表现出高亲和力受体结合。用TRH刺激这些细胞会产生典型的磷酸肌醇反应并使细胞内钙[Ca2+]i动员。
