RGS6/G?5 complex accelerates IKACh gating kinetics in atrial myocytes and modulates parasympathetic regulation of heart rate.
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ABSTRACT:
SUBMITTER: Posokhova E
PROVIDER: S-EPMC3014848 | biostudies-literature | 2010 Nov
REPOSITORIES: biostudies-literature
Publications
RGS6/Gβ5 complex accelerates IKACh gating kinetics in atrial myocytes and modulates parasympathetic regulation of heart rate.
Posokhova Ekaterina E Wydeven Nicole N Allen Kevin L KL Wickman Kevin K Martemyanov Kirill A KA
Circulation research 20100930 11
<h4>Rationale</h4>The parasympathetic reduction in heart rate involves the sequential activation of m2 muscarinic cholinergic receptors (m(2)Rs), pertussis toxin-sensitive (Gi/o) heterotrimeric G proteins, and the atrial potassium channel I(KACh). Molecular mechanisms regulating this critical signal transduction pathway are not fully understood.<h4>Objective</h4>To determine whether the G protein signaling regulator Rgs6/Gβ5 modulates m(2)R-I(KACh) signaling and cardiac physiology.<h4>Methods an ...[more]
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