Effects of volsartan on transmural heterogeneous changes of transient outward potassium currents in hypertrophic cardiomyocytes in rabbits.
- Author:
Jianmin XIAO
1
;
Hui FU
;
Yexin MA
;
Yang LI
;
Zaiying LU
Author Information
1. Department of Cardiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
- Publication Type:Journal Article
- MeSH:
Animals;
Antihypertensive Agents;
pharmacology;
Biological Transport, Active;
drug effects;
Female;
Hypertrophy, Left Ventricular;
drug therapy;
pathology;
Male;
Myocytes, Cardiac;
pathology;
Patch-Clamp Techniques;
Potassium Channels;
drug effects;
Rabbits;
Tetrazoles;
pharmacology;
Valine;
analogs & derivatives;
pharmacology;
Valsartan
- From:
Journal of Huazhong University of Science and Technology (Medical Sciences)
2004;24(5):437-440
- CountryChina
- Language:English
-
Abstract:
The transmural heterogeneous changes of transient outward potassium currents (Ito) in rabbit hypertrophic cardiaomyocytes and the effects of long-term prophylactic treatment with volsartan were investigated. Rabbits were divided into hypertrophy group (left ventricular hypertrophy induced by partial ligation of abdominal aorta), vol-treated group (volsartan was administrated after the ligation), and control group (sham operated). Myocytes were isolated by a two-step enzymatical method. The sub-endocardial (Endo) and sub-epicardium (Epi) tissues were separated from midmyocardium (Mid) with a razor. Whole-cell patch-clamp technique was used to record potassium currents. The results showed that membrane capacitance was larger in hypertrophic cells than those in control and vol-treated cells (P<0.01 vs control cells, n=30). The densities of Ito in hypertrophic cells were reduced by sub-epicardium (Epi) (27.8 +/- 2.9) %, midmyocardium (Mid) (41.0+/-4.7) %, and sub-endocardium (Endo) (20.3 +/- 3.4) % compared with those in control cells. The decrease of Ito density was more pronounced in Mid than in Epi and Endo (P<0.01 vs Epi or Endo). There were no significant differences in Ito densities between vol-treated group and control group in three layers separately. In conclusion, volsartan can inhibit the transmural heterogeneous changes of Ito in left ventricular hypertrophic cardiomyocytes in rabbit.
