α1‐Adrenoceptor‐activated cation currents in neurones acutely isolated from rat cardiac parasympathetic ganglia
α1‐Adrenoceptor‐activated cation currents in neurones acutely isolated from rat cardiac parasympathetic ganglia
复制标题
从大鼠心脏副交感神经节中急性分离的神经元中α1-肾上腺素受体激活的阳离子电流
DOI：
10.1111/j.1469-7793.2003.00111.x
复制
发表时间：
2003
期刊：
影响因子：
--
通讯作者：
N. Akaike
中科院分区：
文献类型：
--
作者：
H. Ishibashi;M. Umezu;I. Jang;Y. Ito;N. Akaike
用制霉菌素穿孔膜片记录技术研究了去甲肾上腺素(NA)对新鲜分离的大鼠心脏副交感神经节神经元的阳离子电流。在电流钳条件下，去甲肾上腺素使膜去极化，引起重复动作电位。在保持电位为−60 mV的电压钳条件下，NA产生内向阳离子电流。胞外Ca~(2+)或Mg~(2+)可抑制Na~(2+)诱发电流，其半峰浓度分别为13μm和1.2 mM。Cirazoline模拟NA的反应，而哌唑嗪和WB-4101抑制NA诱发的电流，提示α1-肾上腺素受体的作用。该电流可被磷脂酶C(PLC)抑制剂U73122抑制。膜通透性IP3受体阻断剂xestospongin-C也阻断了NA诱导的电流。此外，thapsigargin和BAPTA-AM可抑制NA反应，而KN-62、佛波酯和星形孢菌素则无此作用。这些结果表明，NA通过α_1肾上腺素能受体激活新分离的大鼠心脏副交感神经节神经元的细胞外钙和镁敏感阳离子通道。这种激活机制还涉及肌醇磷脂的分解、细胞内钙库中钙离子的释放和钙调蛋白。NA激活的阳离子通道可能在大鼠心脏神经节细胞膜去极化过程中起重要作用。
The noradrenaline (NA)‐induced cation current was investigated in neurones freshly isolated from rat cardiac parasympathetic ganglia using the nystatin‐perforated patch recording configuration. Under current‐clamp conditions, NA depolarized the membrane, eliciting repetitive action potentials. NA evoked an inward cation current under voltage‐clamp conditions at a holding potential of −60 mV. The NA‐induced current was inhibited by extracellular Ca2+ or Mg2+, with a half‐maximal concentration of 13 μm for Ca2+ and 1.2 mm for Mg2+. Cirazoline mimicked the NA response, and prazosin and WB‐4101 inhibited the NA‐induced current, suggesting the contribution of an α1‐adrenoceptor. The NA‐induced current was inhibited by U73122, a phospholipase C (PLC) inhibitor. The membrane‐permeable IP3 receptor blocker xestospongin‐C also blocked the NA‐induced current. Furthermore, pretreatment with thapsigargin and BAPTA‐AM could inhibit the NA response while KN‐62, phorbol 12‐myristate 13‐acetate (PMA) and staurosporine had no effect. These results suggest that NA activates the extracellular Ca2+‐ and Mg2+‐sensitive cation channels via α1‐adrenoceptors in neurones freshly isolated from rat cardiac parasympathetic ganglia. This activation mechanism also involves phosphoinositide breakdown, release of Ca2+ from intracellular Ca2+ stores and calmodulin. The cation channels activated by NA may play an important role in neuronal membrane depolarization in rat cardiac ganglia.
影响因子：
--
作者：
ARDELL, JL;RANDALL, WC
通讯作者：
RANDALL, WC
大鼠心内神经节培养的副交感神经元中离子电流的α-肾上腺素调节。
影响因子：
2.5
作者：
Xu,ZJ;Adams,DJ
通讯作者：
Adams,DJ
去甲肾上腺素对大鼠交感神经元钙电流的差异神经调节。
影响因子：
2.5
作者：
Chen,C;Schofield,GG
通讯作者：
Schofield,GG