Diverse cell morphology and intracellular calcium dynamics in pulmonary vein cardiomyocytes
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : Ming-Chih Yu Chun-Feng Huang Che-Ming Chang Yao-Chang Chen Cheng-I Lin Shih-Ann Chen
- چاپ و سال / کشور: 2010
Description
Pulmonary veins (PVs) contain cardiomyocytes with a complex cellular morphology and high arrhythmogenesis. Ca2? regulation and Ca2? sparks play a pivotal role in the electrical activity of cardiomyocytes. The purpose of this study was to investigate whether the cell morphology can determine the PV electrical activity and Ca2? homeostasis. Through confocal microscopy with fluo-3 Ca2? fluorescence, Ca2? sparks and Ca2? transients were evaluated in isolated single rabbit left atria (LA) and PV cardiomyocytes according to the cell morphology (rod, rod-spindle and spindle/bifurcated). Twenty-two (20%) rod, 49 (43%) rod-spindle and 41 (37%) spindle/bifurcated cardiomyocytes were identified in the LA (n = 29) and PV (n = 83) cardiomyocytes. The PV cardiomyocytes with pacemaker activity had a higher incidence of spindle/ bifurcated morphology than LA and PV cardiomyocytes without pacemaker activity. As compared to those in the rod or rod-spindle cardiomyocytes, spindle/bifurcated cardiomyocytes had a larger Ca2? transient amplitude and higher frequency of the Ca2? sparks with larger amplitude and longer duration. In contrast, rod-spindle and rod cardiomyocytes had similar Ca2? transients and Ca2? sparks. The cell length correlated well with the amplitude of the Ca2? transient and Ca2? spark duration with a linear regression. In conclusion, cell morphology and cell length play a potential role in the Ca2? homeostasis and Ca2? spark. The large Ca2? transients and high frequency of Ca2? sparks in spindle/bifurcated cardiomyocytes may cause a high arrhythmogenesis in the PV cardiomyocytes with pacemaker activity.
Heart Vessels (2011) 26:101–110 DOI 10.1007/s00380-010-0035-y Received: 8 September 2009 / Accepted: 19 February 2010 / Published online: 27 October 2010
