Related Experiment Video
Updated: Aug 10, 2026
11:33
Isolation and Kv Channel Recordings in Murine Atrial and Ventricular Cardiomyocytes
Published on: March 12, 2013
LMNA Deficiency Reveals a Role for SK3 Channel Dysfunction in Atrioventricular Block
Tingting Li1, Xiaolei Wang1, Jia Song1
1Section of Cardiovascular Research, Department of Medicine, Baylor College of Medicine, Houston, Texas, USA.
JACC. Clinical Electrophysiology
|August 8, 2026
Summary
LMNA mutations cause progressive atrioventricular block (AVB) by impairing cardiac pacemaker cells. Activating the SK3 channel offers a potential therapeutic strategy for AVB management.
Area of Science:
- Cardiology
- Genetics
- Molecular Biology
Background:
- Atrioventricular block (AVB) is a heart condition often requiring pacemakers.
- Mutations in the LMNA gene, encoding nuclear envelope proteins lamin A/C, are linked to AVB.
- The precise mechanisms of LMNA-related AVB remain unclear.
Purpose of the Study:
- To investigate the mechanisms of LMNA-R225X mutation-induced AVB.
- To identify potential therapeutic targets for AVB.
Main Methods:
- Generated LMNA-R225X-knock-in mouse models.
- Assessed cardiac function via ECG, electrophysiology, and echocardiography.
- Utilized histology, immunofluorescence, Ca2+ imaging, and RNA sequencing.
Main Results:
- LMNA-R225X mice showed progressive AVB and atrial arrhythmias.
- LMNA deficiency in pacemaker cells induced AVB.
- Down-regulation of the SK3 channel and impaired pacemaker cell automaticity were observed.
- SK3 channel activation attenuated AVB in mouse models.
Conclusions:
- LMNA deficiency directly causes AVB.
- The SK3 channel is a viable therapeutic target for AVB.
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