Reduced Ca2+ transport across sarcolemma but enhanced spontaneous activity in cardiomyocytes isolated from left atrium-pulmonary veins tissue of myopathic hamster
| Autor: | Cheng-I Lin, Yue-Xia Loh, Chih-Hsiung Hsu, Kuo-Ho Wu, Jeng Wei, Yao Chang Chen |
|---|---|
| Jazyk: | angličtina |
| Předmět: |
medicine.medical_specialty
Patch-Clamp Techniques Calcium Channels L-Type Endocrinology Diabetes and Metabolism Clinical Biochemistry Left atrium lcsh:Medicine Hamster chemistry.chemical_element Calcium Sarcolemma Internal medicine Cricetinae medicine Myocyte Animals Myocytes Cardiac Pharmacology (medical) Patch clamp Heart Atria Molecular Biology Heart Failure Biochemistry medical Chemistry Research lcsh:R Biochemistry (medical) Atrial fibrillation General Medicine Cell Biology medicine.disease medicine.anatomical_structure Pulmonary Veins Heart failure Cardiology |
| Zdroj: | Journal of Biomedical Science Journal of Biomedical Science, Vol 16, Iss 1, p 114 (2009) |
| ISSN: | 1423-0127 |
| DOI: | 10.1186/1423-0127-16-114 |
| Popis: | Background Several lines of evidence point to a particularly important role of the left atrium (LA) in initiating and maintaining atrial fibrillation (AF). This role may be related to the location of pulmonary veins (PVs) in the LA. The aim of the present study was to investigate the action potential (AP) and ionic currents in LA-PV cardiomyocytes isolated from Bio14.6 myopathic Syrian hamsters (36-57 week-old) versus age-matched F1B healthy control hamsters. Methods and Results Whole-cell patch-clamp techniques were used to record AP in current-clamp mode and ionic currents in voltage-clamp mode. The results obtained show that in both healthy and myopathic LA-PV tissue spontaneously discharging cardiomyocytes can be found, but they are more numerous in myopathic (9/29) than in healthy hamsters (4/42, p < 0.05 by χ2 analysis). Myopathic myocytes have shorter AP duration (APD) with smaller ICa,L and INCX than the healthy control. The currents ITO, IK, IK1 and ICa,T are not significantly different in myopathic versus healthy cells. Conclusions Our results indicate that in myopathic Syrian hamsters LA-PV cardiomyocytes are more prone to automatic rhythms. Also, they show altered electrophysiologic properties, which may be due to abnormal Ca2+ channels and may account for contractile dysfunction. |
| Databáze: | OpenAIRE |
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