Background: Tropaeolum majus L. (Tropaeolaceae) is an important medicinal plant belonging to the Tropaeolaceae family, which has 80 species distributed in South and Central America. In Brazil, it is distributed practically throughout the entire territory and it is popularly known as “capuchinha”. In folk medicine its leaves are widely used for treatment of cardiovascular disorders. Despite consistent data showing some acute effects on renal and cardiovascular system, no study has investigated whether Tropaeolum majus extracts is able to exert cardiorenal protective effects after 30 days of treatment, i.e. in a sustained manner. Objective: Investigate the prolonged cardiorenal protective effects of ethanolic extract obtained from Tropaeolum majus (EETM) in rats with renovascular hypertension. Material and Methods: First, EETM was obtained and chemically characterized. Then, we investigated the possible antihypertensive and diuretics effects, including effects on renal haemodynamics, after prolonged treatment (30 days) with EETM (3, 30 and 300 mg/kg). Finally, we examined whether treatment with EETM may affect the angiotensin-converting enzyme (ACE) and oxidative stress, preventing heart and kidney damage in two-kidney, one-clip (2K1C) Goldblatt hypertensive rats. Results: Prolonged treatment with EETM was able to prevent the evolution of renovascular hypertension in 2K1C rats, inducing important renoprotective effects and reducing systemic blood pressure and cardiac hypertrophy. Moreover, it was also identified that these effects may be directly related to significant ACE inhibitory activity and reduction of oxidative stress. Conclusion: This study has brought new scientific evidence of preclinical efficacy of EETM as a cardiorenal protective agent in rats with renovascular hypertension.
Key words: Antihypertensive, Cardioprotective, Diuretic, Renoprotective, Tropaeolum majus L.