Effects of electric stimulation applied during absolute refractory period on contraction and relaxation of ventricular myocytes in normal and failure guinea-pigs
- VernacularTitle:绝对不应期电刺激对健康和衰竭豚鼠心室肌细胞舒缩及钙瞬变的影响
- Author:
Xiaojing ZHAO
;
Changcong CUI
;
Haizhu ZHANG
- Publication Type:Journal Article
- Keywords:
electric stimulation applied during absolute refractory period;
ventricular myocytes;
Ca 2+ transient;
guinea-pigs;
chronic heart failure
- From:
Journal of Xi'an Jiaotong University(Medical Sciences)
2003;0(06):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effect of electric stimulation applied during absolute refractory period on contraction and relaxation and Ca 2+ transient of ventricular myocytes from normal guinea-pigs. Methods The ventricular myocytes of guinea-pigs were obtained by enzyme digesting, and the extent of the contraction and relaxation and Ca 2+ transient were recorded through the motion edge detection system. The Ca 2+ transient was reflected by fluorescence ratio (360/380) ( F 360/F 380). Results The ventricular myocytes from the normal guinea-pigs: ①The contraction extent of guinea-pig ventricular myocytes increased by (16.55?5.49)%. The peak velocity of shorting (contraction) and the peak velocity of relengthening (relaxation) increased by (17.43?7.08)% and (19.74?9.08)%, respectively(n=10); ②The extent of F 360/F 380 increased (25.79?6.88)%. The peak velocity of F 360/F 380 increased by (29.47?9.25)% and (22.52?7.81)% during shortening and relengthening, respectively(n=10). The ventricular myocytes from failure guinea-pigs: ①The contraction extent of guinea-pig ventricular myocytes increased by (15.53?5.31)%. The peak velocity of shortening (contraction) and the peak velocity of relengthening (relaxation) increased by (10.60?3.02)% and (23.32?8.26)%, respectively(n=6); ②The extent of F 360/F 380 increased (16.82?7.03)%. The peak velocity of F 360/F 380 increased by (16.27?5.91)% and (10.32?2.46)% during shorenting and relengthening, respectively(n=6). Conclusion Appropriate electric stimulation applied during absolute refractory period might strengthen the contracting and relaxing function of normal and failing ventricular myocytes in guinea-pigs.
