Jw. Carraway et al., Comparison of irbesartan with captopril effects on cardiac hypertrophy andgene expression in heart failure-prone male SHHF/Mcc-fa(cp) rats, J CARDIO PH, 33(3), 1999, pp. 451-460
Citations number
39
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Angiotensin-converting enzyme (ACE) inhibitors have proven an effective mea
ns to control hypertension and manage cardiac hypertrophy. It is presently
unknown if newer specific angiotensin II subtype 1 receptor (AT(1)R) antago
nists are as effective or more effective in treating these conditions compa
red with ACE inhibitors. There is evidence that these classes of drugs may
affect cardiac hypertrophy by different mechanisms. This study compared the
effect of irbesartan, an AT1R antagonist, with that of captopril, an ACE i
nhibitor, on expression of early genetic markers of cardiac hypertrophy in
lean male SHHF/Mcc-fa(cp) rats. SHHF\Mcc-fa(cp) rats (n = 10/group) were gi
ven captopril (100 mg/kg/day), irbesartan (50 mg/kg/day), or placebo for 16
weeks. Irbesartan and captopril significantly reduced systolic pressure an
d produced similar rightward shifts in the angiotensin I dose-response curv
e. Renal renin gene expression was increased 8.6-fold by irbesartan and 17.
7-fold by captopril. The only effect on echocardiographic findings was a si
milar decrease in aortic peak velocity, an index of systolic function, by b
oth treatments. Early markers of cardiac hypertrophy were significantly att
enuated by both drugs. Both drugs produced marked and equivalent reductions
in left ventricular atrial natriuretic peptide (ANP) messenger RNA (mRNA)
levels compared with controls. This decrease in ANP gene expression was acc
ompanied by a decrease in plasma ANP concentration in the treatment groups.
The shift from V-1 to V-3 myosin isozymes was similarly decreased in both
treatment groups, compared with controls. These data suggest that captopril
and irbesartan are similarly effective in controlling expression of genes
associated with ventricular hypertrophy in heart failure-prone SHHF/Mcc-fa(
cp) rat.