Differential regulation of sodium pump α-subunit isoform gene by ouabain and digoxin in myocardium of rats
- VernacularTitle:巴因与地高辛对大鼠心肌钠泵α亚单位哇巴因与地高辛对大鼠心肌钠泵α亚单位基因表达影响的研究
- Author:
Weiqing YUAN
;
Hao WANG
;
Zhuoren L
- Publication Type:Journal Article
- From:
Chinese Journal of Internal Medicine
2001;40(2):105-108
- CountryChina
- Language:Chinese
-
Abstract:
Objective To compare the effects of ouabain and digoxin on both the systolic blood pressure (SBP) and sodium pump α-subunit expression in myocardium of rats. Methods Normal Sprague-Dawley (SD) rats were injected with ouabain, digoxin or normal saline (NS) everyday and indirect SBP was recorded once a week. Six weeks later, all the rats were killed and sodium pump α1-, α2-, and α3-subunit were detected in the left ventricular myocardium with RT-PCR method and immunohistochemical assay at mRNA and protein levels. Results At the end of six weeks SBP of rats infused with ouabain increased significantly (132.6±9.0 vs 115.7±8.2 mm Hg， P＜0.01), while no difference of SBP was found between digoxin group and NS group. The effects of ouabain and digoxin on sodium pump α-subunit isoform expression in myocardium were also different: both ouabain and digoxin stimulated expression of α3-isoform whereas α2-isoform unchanged at both mRNA and protein levels. α1-isoform was decreased in ouabain group and α1-isoform unchanged in digoxin group at both mRNA and protein levels. Conclusion It is suggested that both ouabain and digoxin could regulate sodium pump α-subunit isoform expression, which might be related to the physiological roles of endogenous ouabain and might be responsible for the difference between the pharmacological and toxicological effects of ouabain and digoxin, including their effects on blood pressure.
