非洲爪蟾卵母细胞中大鼠KV1.2的受体介导调节

Receptor-mediated modulation of rat KV1.2 in Xenopus oocytes.

作者信息

Murakoshi H, Ishii K, Nunoki K, Taira N

机构信息

Department of Pharmacology, Tohoku University School of Medicine, Sendai, Japan.

出版信息

Eur J Pharmacol. 1994 Aug 16;268(3):451-4. doi: 10.1016/0922-4106(94)90073-6.

DOI:10.1016/0922-4106(94)90073-6

PMID:7805772

Abstract

To investigate mechanisms for the receptor-mediated inhibition of a rat cardiac K+ channel clone (KV1.2), we coexpressed KV1.2 with a subtype of endothelin receptors (ETA) in Xenopus oocytes. Effects of endothelin ETA receptor stimulation were mimicked by application of PMA (4-beta-phorbol 12-myristate 13-acetate; 0.1 microM) or intracellular injection of CaCl2 (estimated concentration of 1 microM). These effects diminished in the presence of staurosporine (1 microM) or EGTA (estimated concentration of 5 mM). These results suggest that both activation of protein kinase C and an increase in intracellular Ca2+ contribute to the suppression.

摘要

为了研究受体介导的对大鼠心脏钾通道克隆体（KV1.2）抑制作用的机制，我们在非洲爪蟾卵母细胞中将KV1.2与内皮素受体的一个亚型（ETA）共表达。应用佛波酯（4-β-佛波醇12-肉豆蔻酸酯13-乙酸酯；0.1微摩尔）或细胞内注射氯化钙（估计浓度为1微摩尔）可模拟内皮素ETA受体刺激的作用。在存在星形孢菌素（1微摩尔）或乙二醇双（2-氨基乙基醚）四乙酸（估计浓度为5毫摩尔）的情况下，这些作用减弱。这些结果表明，蛋白激酶C的激活和细胞内钙离子的增加均有助于这种抑制作用。