Activation of muscarinic K+ current by β‐adrenergic receptors in cultured atrial myocytes transfected with β1 subunit of heterotrimeric G proteins

FEBS Letters

Bender, Kirsten¹  Pott, Lutz¹  Wellner-Kienitz, Marie-Cécile¹  Meyer, Thomas¹ 

[1] Institut für Physiologie, Abteilung Zelluläre Physiologie, Ruhr-Universität Bochum, D-44780 Bochum, Germany

关键词: Potassium channel;    G protein;    Beta receptor;    GIRK;    Cardiac cell;   

DOI  :  10.1016/S0014-5793(98)01350-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Muscarinic K⁺ channels (I_K(ACh)) in native atrial myocytes are activated by βγ subunits of pertussis toxin (Ptx)-sensitive heterotrimeric G proteins coupled to different receptors. βγ subunits of Ptx-insensitive G_s, coupled to β-adrenergic receptors, do not activate native I_K(ACh). In atrial myocytes from adult rats transfected with rat brain β₁ subunit I_K(ACh) can be activated by stimulation of β-adrenergic receptors using isoprenaline. This effect is insensitive to Ptx. These findings demonstrate for the first time promiscuous (Ptx-insensitive) coupling of G_sβγ to GIRK channels in their native environment.

【 授权许可】

Unknown