Ca(2+)-Clock-Dependent Pacemaking in the Sinus Node Is Impaired in Mice with a Cardiac Specific Reduction in SERCA2 Abundance.

ABSTRACT:

Background

The sarcoplasmic reticulum Ca(2+)-ATPase (SERCA2) pump is an important component of the Ca(2+)-clock pacemaker mechanism that provides robustness and flexibility to sinus node pacemaking. We have developed transgenic mice with reduced cardiac SERCA2 abundance (Serca2 KO) as a model for investigating SERCA2's role in sinus node pacemaking.

Methods and results

In Serca2 KO mice, ventricular SERCA2a protein content measured by Western blotting was 75% (P < 0.05) lower than that in control mice (Serca2 FF) tissue. Immunofluorescent labeling of SERCA2a in ventricular, atrial, sinus node periphery and center tissue sections revealed 46, 45, 55, and 34% (all P < 0.05 vs. Serca2 FF) lower labeling, respectively and a mosaic pattern of expression. With telemetric ECG surve

SUBMITTER: Logantha SJ 

PROVIDER: S-EPMC4889599 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature