- 作者： Yue-Xia Loh; Kuo-Ho Wu; Yao-Chang Chen; Chih-Hsiung Hsu; Jeng Wei; Cheng-I Lin
- 作者服務機構： Institute of Physiology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, R.O.C.
- 中文摘要： --
- 英文摘要：
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 2
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. - 中文關鍵字： --
- 英文關鍵字： --
