Regulation of muscarinic receptor-mediated cyclic GMP synthesis by cultured mouse neuroblastoma cells.
Regulation of muscarinic receptor-mediated cyclic GMP synthesis by cultured mouse neuroblastoma cells.
复制标题
培养的小鼠神经母细胞瘤细胞对毒蕈碱受体介导的环 GMP 合成的调节。
DOI：
10.1111/j.1471-4159.1980.tb07093.x
复制
发表时间：
1980
影响因子：
4.7
通讯作者：
Richelson,E
中科院分区：
文献类型：
--
作者：
El-Fakahany,E;Richelson,E
小鼠神经母细胞瘤克隆N1 E-115具有介导环GMP合成的毒蕈碱乙酰胆碱受体。这种受体介导的反应在细胞维持在稳定期至少1周之前不会显著高于背景。研究了培养时间对环鸟苷酸反应影响的基础。通过用[3 H]鸟嘌呤放射性标记GTP池，用激动剂孵育细胞，然后色谱分离[3 H]环GMP，测量由完整细胞合成的环GMP的相对量。氨甲酰胆碱、离子载体X-537 A-和叠氮化钠诱导的环GMP形成在培养中随时间增加，最大分别为基础水平的13倍、9倍和2.5倍。通过[3 H]奎宁环苄酯（[3 H]QNB）结合测定，毒蕈碱受体的数量或表观亲和力无变化。此外，通过测定氨甲酰胆碱取代[3 H]QNB特异性结合的能力，受体对激动剂的表观亲和力没有变化。从第0天到第22天，每毫克蛋白质和每个细胞的鸟苷酸环化酶活性分别增加了6倍和7倍。然而，鸟苷酸环化酶的这种增加似乎先于细胞对激动剂的敏感性的显著增加。这些数据表明，除了鸟苷酸环化酶和毒蕈碱受体外，还有另一种因素负责这种毒蕈碱受体介导的反应的发展。
Mouse neuroblastoma clone N1E‐115 has muscarinic acetylcholine receptors that mediate cyclic GMP synthesis. This receptor‐mediated response is not significantly higher than background until the cells have been maintained in the stationary phase for at least 1 week. The basis of the influence of time in culture on the cyclic GMP response was investigated. The relative amount of cyclic GMP synthesized by intact cells was measured by radioactively labeling the GTP pool with [3H]guanine, incubating cells with agonists, and then chromatographically isolating [3H]cyclic GMP. Carbamylcholine‐, ionophore X‐537A‐, and sodium azide‐induced cyclic GMP formation increased with time in culture to a maximum of 13‐, 9‐, and 2.5‐fold above basal, respectively. There was no change in the number or the apparent affinity of the muscarinic receptors as measured by [3H]quinuclidinyl benzylate ([3H]QNB) binding. In addition, there was no change in the apparent affinity of the receptors for agonist as measured by the ability of carbamylcholine to displace the specific binding of [3H]QNB. Guanylate cyclase activity per milligram protein and per cell in‐creased six‐ and sevenfold, respectively, from day 0 to day 22. However, this increase in guanylate cyclase appeared to precede the marked increase in sensitivity of the cells to agonists. These data suggest that, in addition to guanylate cyclase and muscarinic receptors, there is another factor which is responsible for the development of this muscarinic receptor‐mediated response.