Combined effects of low-dose spironolactone and captopril therapy in a rat model of genetic hypertrophic cardiomyopathy.
For several years, the severe side effects associated with the use of high doses of the aldosterone antagonist, spironolactone, limited its clinical use. Studies have recently shown efficacy and minimal side effects of low-dose spironolactone combined with standard therapy in the treatment of heart failure and hypertensive patients. The authors evaluated the effects of low-dose spironolactone alone or in combination with angiotensin-converting enzyme (ACE) inhibitors on the progression of left ventricular dysfunction and remodeling in a congenic rat model of hypertrophic cardiomyopathy. The congenic SS-16/Mcwi rats developed severe cardiac hypertrophy despite being normotensive even on high-salt diet. SS-16/Mcwi and SS/Mcwi rats were fed a low-salt (0.4% NaCl) diet and were treated with vehicle (CON), spironolactone (20 mg/kg/d subcutaneously), captopril (100 mg/kg/d drinking water), or both spironolactone and captopril for 4 weeks. Blood pressure, plasma peptides, cardiac fibrosis, and echocardiography measurements were evaluated. Spironolactone at a low dose had no effect on blood pressure, cardiac hypertrophy, and fibrosis in either strain. However, in combination with captopril, spironolactone decreased the cardiac hypertrophy more than captopril treatment alone. In the SS-16/Mcwi rats, the combined therapy significantly preserved the cardiac index when compared with control. These data indicate that the addition of low-dose spironolactone to captopril treatment was more effective in preventing the progression of heart hypertrophy and ventricular dysfunction in the SS-16/Mcwi than captopril alone. This study suggests that combined spironolactone and captopril therapy may be useful in the treatment of hypertrophic cardiomyopathy.
de Resende
Micheline Monteiro
MM
Biotechnology and Bioengineering Center, Department of Physiology, Medical College of Wisconsin, Milwaukee, WI, USA.
Kriegel
Alison Jessica
AJ
Greene
Andrew Seth
AS
D000284:Administration, Oral; D000450:Aldosterone / Q000097:blood; D000804:Angiotensin II / Q000097:blood; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use; D000818:Animals; D020296:Animals, Congenic; D009320:Atrial Natriuretic Factor / Q000097:blood; D001794:Blood Pressure / Q000187:drug effects; D002216:Captopril / Q000008:administration & dosage / Q000627:therapeutic use*; D002312:Cardiomyopathy, Hypertrophic / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D004195:Disease Models, Animal; D004232:Diuretics / Q000008:administration & dosage / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D004452:Echocardiography / Q000379:methods; D007279:Injections, Subcutaneous; D009206:Myocardium / Q000473:pathology; D009929:Organ Size / Q000187:drug effects; D011897:Random Allocation; D051381:Rats; D011919:Rats, Inbred Strains; D013148:Spironolactone / Q000008:administration & dosage / Q000627:therapeutic use*; D016277:Ventricular Function, Left / Q000187:drug effects; D015431:Weight Loss / Q000187:drug effects
D000806:Angiotensin-Converting Enzyme Inhibitors; D004232:Diuretics; C472610:atrial natriuretic peptide, rat; D000804:Angiotensin II; D013148:Spironolactone; D000450:Aldosterone; D009320:Atrial Natriuretic Factor; D002216:Captopril