Acetylcholine sensitivity of cat petrosal ganglion neurons.
Acetylcholine sensitivity of cat petrosal ganglion neurons.
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猫岩神经节神经元的乙酰胆碱敏感性。
DOI：
10.1007/0-306-46825-5_35
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发表时间：
2000
影响因子：
--
通讯作者：
Fitzgerald,RS
中科院分区：
文献类型：
--
作者：
Shirahata,M;Ishizawa,Y;Rudisill,M;Sham,JS;Schofield,B;Fitzgerald,RS
我们研究了神经元烟碱乙酰胆碱受体（nAChR）是否位于猫岩神经节（PG）的化学感受器传入神经元中，以及乙酰胆碱（ACh）是否兴奋化学感受器传入神经元。免疫细胞化学显示，大多数PG神经元表达神经元nAChR的α4和/或α7亚基，其中部分酪氨酸羟化酶阳性。使用膜片钳技术（全细胞配置）研究培养的 PG 神经元的兴奋性。乙酰胆碱和尼古丁会引起内向和外向电流。通过去除细胞外钙和α4β2（二氢-β-赤霉素）或α7 nAChR（甲基lycaconitine）拮抗剂部分阻断内向电流。外向电流被 4-氨基吡啶 (4-AP) 阻断，有时也被阿托品阻断。乙酰胆碱诱导的膜电位变化与乙酰胆碱诱导的电流密切相关。对乙酰胆碱的反应发生去极化和超极化。有时，去极化之后会出现一系列动作电位。结果表明，异质神经元 nAChR 广泛分布于化学感受器和其他 PG 神经元中。在一些神经元中，nAChR 可能在没有 K 通道的情况下进行功能耦合。需要进一步的研究来确定化学感受器神经元是否具有独特的 nAChR 和 K+ 通道分布模式。
We investigated if neuronal nicotinic acetylcholine receptors (nAChRs) are localized in chemoreceptor afferent neurons in the cat petrosal ganglion (PG) and if acetylcholine (ACh) excites chemoreceptor afferent neurons. Immunocytochemistry revealed that a majority of PG neurons expressed α4 and/or α7 subunits of neuronal nAChRs, and a part of them were tyrosine hydroxylase positive. Excitability of cultured PG neurons was studied with patch clamp techniques (whole cell configuration). ACh and nicotine evoked both inward and outward currents. The inward current was partiallyblocked by removal of extracellular calcium and by antagonists for α4β2 (dihydro-β-erythroidine) or α7 nAChRs (methyllycaconitine). Outward current was blocked by 4-aminopyridine (4-AP) and sometimes by atropine. ACh-induced membrane potential changes were well correlated with ACh-induced currents. Depolarization and hyperpolarization occurred in response to ACh. Occasionally depolarization was followed by a train of action potentials. The results suggest that heterogeneous neuronal nAChRs are widely distributed in both chemoreceptor and other PG neurons. In some neurons nAChRs may be functionally coupled withoutward K-channels. Further studies are required to determine whether chemoreceptor neurons have a distinct distribution pattern of nAChRs and K+channels.