RGS6/Gβ5 complex accelerates IKACh gating kinetics in atrial myocytes and modulates parasympathetic regulation of heart rate.

ABSTRACT:

Rationale

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.

Objective

To determine whether the G protein signaling regulator Rgs6/Gβ5 modulates m(2)R-I(KACh) signaling and cardiac physiology.

Methods and results

Cardiac expression of Rgs6, and its interaction with Gβ5, was demonstrated by immunoblotting and immunoprecipitation. Rgs6(-/-) mice were generated by gene targeting, and the cardiac effects of Rgs6 ablation were analyzed by whole-cell recordings in isolated cardiomyocytes and ECG tele

SUBMITTER: Posokhova E 

PROVIDER: S-EPMC3014848 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature