Hermans E, Maloteaux J M, Octave J N
Laboratoire de Neurochimie, Université Catholique de Louvain, Brussels, Belgium.
Brain Res Mol Brain Res. 1992 Oct;15(3-4):332-8. doi: 10.1016/0169-328x(92)90126-v.
The rat neurotensin receptor cDNA sequence was transfected in Chinese hamster ovary cells and cellular clones which stably express the corresponding protein were isolated and characterized. The Scatchard analysis of the specific binding of [3H]neurotensin indicated a Kd value of 0.45 +/- 0.08 nM and a Bmax value of 3.27 +/- 0.29 pmol/mg of protein. Displacement experiments using peptidic analogs of neurotensin and levocabastine confirmed that the transfected receptor exhibits the binding properties of the neurotensin receptor characterized in the rat brain. Neurotensin stimulated the phosphoinositides hydrolysis in a time- and concentration-dependent manner and this effect was mimicked by neurotensin(8-13) and by neuromedin N. The stimulation of phosphoinositides hydrolysis was not inhibited by pertussis toxin. These results indicate that the transfected cells actively express the rat neurotensin receptor which is functionally coupled to phospholipase C through a pertussis toxin-insensitive GTP-binding protein, and that neuromedin N is able to induce the phosphoinositides turnover by interaction with the neurotensin receptor.
将大鼠神经降压素受体cDNA序列转染至中国仓鼠卵巢细胞中，分离并鉴定出稳定表达相应蛋白的细胞克隆。对[3H]神经降压素特异性结合的Scatchard分析表明，解离常数（Kd）值为0.45±0.08 nM，最大结合容量（Bmax）值为3.27±0.29 pmol/mg蛋白。使用神经降压素的肽类似物和左卡巴斯汀进行的置换实验证实，转染的受体具有在大鼠脑中所表征的神经降压素受体的结合特性。神经降压素以时间和浓度依赖性方式刺激磷酸肌醇水解，神经降压素（8 - 13）和神经介素N可模拟这种效应。百日咳毒素不抑制磷酸肌醇水解的刺激作用。这些结果表明，转染的细胞积极表达大鼠神经降压素受体，该受体通过对百日咳毒素不敏感的GTP结合蛋白与磷脂酶C功能偶联，并且神经介素N能够通过与神经降压素受体相互作用诱导磷酸肌醇周转。
