Administration of Sar1,Ile8-AII and Sar1,Ala8-AII produced a significant increase in heart weight and ventricular catecholamine concentration in normotensive rats, prevented by adrenalectomy.
Do Angiotensin II antagonists affect cardiac hypertrophy in normotensive rats?
Certain Angiotensin II antagonists induce cardiac hypertrophy in normotensive rats, an effect that appears to be modulated by catecholamines.
Angiotensin II (AII) antagonists, namely Sar1,Ile8-AII, Sar1,Ala8-AII and Sar1,Thr8-AII, were administered daily for 4 weeks to normotensive rats to study their effect on cardiac hypertrophy. 2. None of the antagonists altered blood pressure significantly but Sar1,Ile8-AII and Sar1,Ala8-AII produced a significant increase in heart weight, as compared with untreated age-matched control rats. Administration of Sar1,Thr8-AII did not produce cardiac hypertrophy. 3. A significant increase in catecholamine concentration was observed in the ventricles of rats treated with Sar1,Ile8-AII and Sar1,Ala8-AII but no change was found in the group treated with the Sar1,Thr8-AII analogue. The production of cardiac hypertrophy by Sar1,Ile8-AII was prevented by bilateral adrenalectomy, suggesting an important role for catecholamines in modulating cardiac hypertrophy.
Sen et al. (1979) studied Normotensive rats. Angiotensin II (AII) antagonists (Sar1,Ile8-AII, Sar1,Ala8-AII and Sar1,Thr8-AII) vs. Untreated age-matched control rats was evaluated on Cardiac hypertrophy (heart weight) and catecholamine concentration. Administration of Sar1,Ile8-AII and Sar1,Ala8-AII produced a significant increase in heart weight and ventricular catecholamine concentration in normotensive rats, prevented by adrenalectomy.