Source
Key Laboratory of Viral Heart Diseases of Ministry of Health, Zhongshan Hospital of Shanghai Medical University, Shanghai Institute of Cardiovascular Diseases, Shanghai 200032, China.
Abstract
OBJECTIVE:
To investigate the effect of coxsackievirus B3 (CVB3) on intracellular calcium, L type voltage dependent calcium channel (VDCC) and Na+/Ca2+ exchange (NCE) in adult rat cardiomyocytes.
METHODS:
Rat hearts were perfused with collagenase to gain single cardiomyocyte. The intracellular free calcium concentration of the cardiomyocytes were detected by laser confocal microscopy with calcium indicator, Fluo3-acetoxymethyl ester; and the currents of VDCC, Na+ and NCE were recorded by patch clamp techniques.
RESULTS:
The free intracellular calcium concentration increased from (51 +/- 43) nmo1/L in normal cardiomyocytes to (339 +/- 208) nmo1/L in CVB3 infected cardiomyocytes. The VDCC current increased from (4.13 +/- 0.75) pA/pF to (4.9 +/- 1.4) pA/pF after CVB3 infection, and the inward NEC current decreased from (-0.46 +/- 0.21) pA/pF to (-0.28 +/- 0.16) pA/pF; besides, the reverse potential of NCE was shifted from (29.4 +/- 7.0) mV to (41 +/- 14) mV with CVB3 infection.
CONCLUSIONS:
The increase of L type VDCC current and decrease of inward NCE current with shift of NCE reverse potential may partly attribute to intracellular free calcium accumulation; also, it may be the cause of cell damage and the occurrence of abnormal electric activities induced by CVB3 infection.