Logo Medical Science Monitor

Call: +1.631.470.9640
Mon - Fri 10:00 am - 02:00 pm EST

Contact Us

Logo Medical Science Monitor Logo Medical Science Monitor Logo Medical Science Monitor

08 May 2018 : Laboratory Research  

Ca2+/Calmodulin-Dependent Protein Kinase II (CaMKII) Increases Small-Conductance Ca2+-Activated K+ Current in Patients with Chronic Atrial Fibrillation

Xuehui FanBD, Yiyan YuBC, Huan LanBC, Xianhong OuBD, Lijie YangBF, Tao LiBC, Jiming CaoEF, Xiaorong ZengEF, Miaoling LiAEG

DOI: 10.12659/MSM.909684

Med Sci Monit 2018; 24: LBR3011-3023


BACKGROUND: Increased small-conductance Ca2+-activated K+ current (SK), abnormal intracellular Ca2+ handling, and enhanced expression and activity of Ca2+/calmodulin-dependent protein kinase II (CaMKII) have been found in clinical and/or experimental models of atrial fibrillation (AF), but the cumulative effect of these phenomena and their mechanisms in AF are still unclear. This study aimed to test the hypothesis that CaMKII increases SK current in human chronic AF.

MATERIAL AND METHODS: Right atrial appendage tissues from patients with either sinus rhythm (SR) or AF and neonatal rat atrial myocytes were used. Patch clamp, qRT-PCR, and Western blotting techniques were used to perform the study.

RESULTS: Compared to SR, the apamin-sensitive SK current (IKAS) was significantly increased, but the mRNA and protein levels of SK1, SK2, and SK3 were significantly decreased. In AF, the steady-state Ca2+ response curve of IKAS was shifted leftward and the [Ca2+]i level was significantly increased. CaMKII inhibitors (KN-93 or autocamtide-2-related inhibitory peptide (AIP)) reduced the IKAS in both AF and SR. The inhibitory effect of KN-93 or AIP on IKAS was greater in AF than in SR. The expression levels of calmodulin, CaMKII, and autophosphorylated CaMKII at Thr287 (but not at Thr286) were significantly increased in AF. Furthermore, KN-93 inhibited the expression of (Thr287)p-CaMKII and SK2 in neonatal rat atrial myocytes.

CONCLUSIONS: SK current is increased via the enhanced activation of CaMKII in patients with AF. This finding may explain the difference between SK current and channels expression in AF, and thus may provide a therapeutic target for AF.

Keywords: Atrial Fibrillation, Calcium-Calmodulin-Dependent Protein Kinase Type 2, Phosphorylation, Small-Conductance Calcium-Activated Potassium Channels



01 November 2021 : Editorial  

Editorial: What Can be Learned from National and International Vaccine Adverse Event Reporting Systems During the COVID-19 Pandemic?

Dinah V. Parums
Scientific Editor, Medical Science Monitor, International Scientific Information, Inc., Melville, NY, USA

DOI: 10.12659/MSM.935299

Med Sci Monit 2022; 28:e935299


26 November 2021 : Editorial  

Editorial: SARS-CoV-2 Vaccine Responses and Breakthrough COVID-19

Med Sci Monit In Press; DOI: 10.12659/MSM.935624  

08 November 2021 : Database Analysis  

Virtual Screening and Molecular Docking to Study the Mechanism of Chinese Medicines in the Treatment of Cor...

Med Sci Monit In Press; DOI: 10.12659/MSM.934102  

25 November 2021 : Clinical Research  

Use of Monoclonal Antibodies Therapy for Treatment of Mild to Moderate COVID-19 in 4 Patients with Rheumato...

Med Sci Monit 2021; 27:e934267

In Press

26 Nov 2021 : Clinical Research  

Serum Uric Acid Levels in Relation to Atrial Fibrillation: A Case-Control Study

Med Sci Monit In Press; DOI: 10.12659/MSM.934007  

26 Nov 2021 : Database Analysis  

Network Pharmacology Integrated Molecular Docking Revealed the Mechanism of Jianpi Yiqi Taohua Decoction Ag...

Med Sci Monit In Press; DOI: 10.12659/MSM.933537  

26 Nov 2021 : Editorial  

Editorial: SARS-CoV-2 Vaccine Responses and Breakthrough COVID-19

Med Sci Monit In Press; DOI: 10.12659/MSM.935624  

26 Nov 2021 : Review article  

A Review of Circulating Tumor DNA in the Diagnosis and Monitoring of Esophageal Cancer

Med Sci Monit In Press; DOI: 10.12659/MSM.934106  

Most Viewed Current Articles

20 Mar 2020 : Clinical Research  

Social Capital and Sleep Quality in Individuals Who Self-Isolated for 14 Days During the Coronavirus Diseas...

DOI :10.12659/MSM.923921

Med Sci Monit 2020; 26:e923921

15 Apr 2020 : Clinical Research  

Psychological Impact and Coping Strategies of Frontline Medical Staff in Hunan Between January and March 20...

DOI :10.12659/MSM.924171

Med Sci Monit 2020; 26:e924171

05 May 2020 : Review article  

An Evidence Based Perspective on mRNA-SARS-CoV-2 Vaccine Development

DOI :10.12659/MSM.924700

Med Sci Monit 2020; 26:e924700

26 Apr 2020 : Clinical Research  

Comparison of Prevalence and Associated Factors of Anxiety and Depression Among People Affected by versus P...

DOI :10.12659/MSM.924609

Med Sci Monit 2020; 26:e924609

Your Privacy

We use cookies to ensure the functionality of our website, to personalize content and advertising, to provide social media features, and to analyze our traffic. If you allow us to do so, we also inform our social media, advertising and analysis partners about your use of our website, You can decise for yourself which categories you you want to deny or allow. Please note that based on your settings not all functionalities of the site are available. View our privacy policy.

Medical Science Monitor eISSN: 1643-3750
Medical Science Monitor eISSN: 1643-3750