Proadrenomedullin N-terminal 20 peptide hyperpolarizes the membrane by activating an inwardly rectifying K+ current in differentiated PC12 cells.
Proadrenomedullin N-terminal 20 peptide hyperpolarizes the membrane by activating an inwardly rectifying K+ current in differentiated PC12 cells.
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肾上腺髓质素原 N 端 20 肽通过激活分化的 PC12 细胞中的内向整流 K 电流使细胞膜超极化。
DOI：
10.1161/01.res.84.4.445
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发表时间：
1999
影响因子：
20.1
通讯作者：
T. Fujita
中科院分区：
文献类型：
--
作者：
K. Takano;T. Fujita
为探讨肾上腺髓质素N-末端20肽(PAMP)抑制肾上腺素能神经中儿茶酚胺释放的作用机制，用神经生长因子处理与去甲肾上腺素能神经元有相似分化特征的PC12细胞。用穿孔全细胞钳技术观察PAMP对这些细胞兴奋性的影响。PAMP以剂量依赖的方式增加K+电导，使膜超极化。PAMP诱导的K+电导的电流-电压关系(I-V)呈内向整流。向细胞内微量注射GDPbetaS或用百日咳毒素预处理细胞可取消这种激活。这些结果表明，百日咳毒素敏感的G蛋白参与了信号转导。微量注射抗Galphai3羧基末端抗体可减弱PAMP对K+电导的激活作用，但不影响Galphai1和Galphai2共同羧基末端抗体的激活作用，提示将PAMP受体偶联到内向整流性K+电流的G蛋白为Galphai3。PAMP诱导的超极化可能通过抑制动作电位频率而抑制神经元儿茶酚胺的释放。
The mechanism of proadrenomedullin N-terminal 20 peptide (PAMP)-induced inhibition of catecholamine release from adrenergic nerve was investigated in nerve growth factor-treated PC12 cells that have differentiated characteristics somewhat similar to noradrenergic neurons. The effect of PAMP on the excitability of these cells was investigated with the use of perforated whole-cell clamp. PAMP hyperpolarized the membrane by increasing a K+ conductance in a dose-dependent manner. The current-voltage relationship (I-V) relationship of the PAMP-induced K+ conductance exhibited inward-going rectification. The activation was abolished by microinjecting GDPbetaS into the cells or pretreating the cells with pertussis toxin. These results indicate that a pertussis toxin-sensitive G protein is involved in the signal transduction. The PAMP-induced activation of the K+ conductance was attenuated by microinjecting antibody against the carboxyl terminus of Galphai3, but it was not influenced by microinjecting antibody against the common carboxyl termini of Galphai1 and Galphai2, which indicated that the G protein coupling the PAMP receptor to the inwardly rectifying K+ current is Galphai3. The PAMP-induced hyperpolarization may inhibit the catecholamine release from the neurons by attenuating the action potential frequency.
对 G 蛋白 α 或 β 亚基具有确定特异性的合成肽抗血清。
影响因子：
--
作者：
Mumby,SM;Gilman,AG
通讯作者：
Gilman,AG
P 物质和生长抑素通过不同的 G 蛋白途径抑制大鼠交感神经元中的钙通道。
影响因子：
16.2
作者：
Shapiro,MS;Hille,B
通讯作者：
Hille,B