Electrophysiology of T lymphocyte cholinergic receptors.
Electrophysiology of T lymphocyte cholinergic receptors.
复制标题
T 淋巴细胞胆碱能受体的电生理学。
DOI：
10.1073/pnas.77.7.4317
复制
发表时间：
1980
影响因子：
11.1
通讯作者：
Strom,TB
中科院分区：
文献类型：
--
作者：
Shapiro,HM;Strom,TB
功能性毒蕈碱胆碱能受体在至少一些T淋巴细胞上的存在表明，在富含T细胞的细胞悬浮液中存在可饱和的、高亲和力的、特异性的毒蕈碱结合，但在富含B细胞的细胞悬浮液中不存在，并且观察到对淋巴细胞的胆碱能作用（例如，与毒蕈碱剂预孵育的细胞毒性淋巴细胞的裂解能力增加）。在本研究中，我们使用流式细胞术和膜电位荧光探针（花青染料 3,3'-二己基氧羰花青碘化物）来检查胆碱能激动剂和拮抗剂对富含 T 细胞和 B 细胞的悬浮液中淋巴细胞膜电位的影响。乙酰胆碱 (AcCho) 和氨基甲酰胆碱 (CbmCho) 可使 T 细胞膜去极化，但不会使 B 细胞膜去极化；最大去极化由 10 nM AcCho 或 1 nM CbmCho 产生。暴露于这些浓度的激动剂后5-8分钟去极化达到最大； T 细胞膜电位在 13-15 分钟后恢复到对照值。 100 nM AcCho 和 10 nM CbmCho 产生不太明显的去极化； 100 pM CbmCho 的效果仅略低于 1 nM CbmCho，并且去极化在暴露后持续 12 分钟。当 AcCho 与 10 nM 阿托品组合时，1 nM AcCho 诱导的去极化被消除，但当 AcCho 与 1 nM 阿托品或 200 nM d-筒箭毒碱组合时则不会。膜电位响应的时间过程及其对 AcCho 和特定胆碱能阻断剂相对浓度的依赖性与结合研究和生物效应密切相关。我们的结果证明 T 淋巴细胞具有功能性毒蕈碱受体；流式细胞术应该普遍适用于受体-配体相互作用的电生理学和药理学研究。
The presence of functional muscarinic-cholinergic receptors on at least some T lymphocytes is suggested by the existence of saturable, high-affinity, specific muscarinic binding in T cell-enriched, but not in B cell-enriched, cell suspensions and by observed cholinergic effects on lymphocytes, (e.g., increased lytic capacity of cytotoxic lymphocytes preincubated with muscarinic agents). In this study, we used flow cytometry and a fluorescent probe of membrane potential, the cyanine dye 3,3'-dihexyloxacarbocyanine iodide, to examine the effects of cholinergic agonists and antagonists on the membrane potentials of lymphocytes in T cell-enriched and B cell-enriched suspensions. Acetylcholine (AcCho) and carbamoylcholine (CbmCho) depolarized the membranes of T cells, but not of B cells; the maximal depolarization was produced by 10 nM AcCho or by 1 nM CbmCho. Depolarization following exposure to these concentrations of agonists was maximal by 5-8 min; T cell membrane potentials returned to control values by 13-15 min. Less marked depolarization was produced by 100 nM AcCho and 10 nM CbmCho; 100 pM CbmCho was only slightly less effective than 1 nM CbmCho, and the depolarization persisted 12 min after exposure. Depolarization induced by 1 nM AcCho was abolished when AcCho was combined with 10 nM atropine but not when AcCho was combined with 1 nM atropine or 200 nM d-tubocurarine. The time course of the membrane potential response and its dependence on the relative concentrations of AcCho and specific cholinergic blocking agents correlate well with both binding studies and biological effects. Our results provide evidence that T lymphocytes have functional muscarinic receptors; the flow cytometric method should be generally applicable to studies of the electrophysiology and pharmacology of receptor-ligand interactions.