Effect of felodipine on myocardial and renal injury induced by aldosterone-high salt hypertension in uninephrectomized rats

• Published in: Brazilian journal of medical and biological research 2010-05, Vol.43 (5), p.506-514
• Main Authors: Matsubara, B B, Franco, M, Janicki, J S, Matsubara, L S
• Format: Article
• Language: English
• Subjects: Aldosterone; Aldosterone - pharmacology; Animals; BIOLOGY; Blood Pressure - drug effects; Calcium Channel Blockers - therapeutic use; Dihydropyridine; Disease Models, Animal; Felodipine - therapeutic use; Fibrinoid necrosis; Fibrosis - prevention & control; Hypertension; Hypertension - drug therapy; Hypertension - pathology; Kidney - pathology; MEDICINE, RESEARCH & EXPERIMENTAL; Myocardial remodeling; Myocardium - pathology; Necrosis - prevention & control; Nephrectomy; Rats; Rats, Wistar; Sodium Chloride; Vascular remodeling
• ISSN: 0100-879X; 1414-431X; 1414-431X; 0100-879X
• DOI: 10.1590/S0100-879X2010007500037

It has been recently shown that calcium channel blockers might have a protective effect on cardiac fibrogenesis induced by aldosterone. The objective of this study was to evaluate the protective effect of felodipine, a dihydropyridine calcium channel blocker, against heart and kidney damage caused by aldosterone-high sodium intake in uninephrectomized rats. Wistar rats were divided into three groups: CNEP (uninephrectomized + 1% NaCl in the drinking water, N = 9); ALDO (same as CNEP group plus continuous infusion of 0.75 microg/h aldosterone, N = 12); ALDOF (same as ALDO group plus 30 mg*kg(-1)*day(-1) felodipine in the drinking water, N = 10). All results were compared with those of age-matched, untreated rats (CTL group, N = 10). After 6 weeks, tail cuff blood pressure was recorded and the rats were killed for histological analysis. Blood pressure (mmHg) was significantly elevated (P < 0.05) in ALDO (180 +/- 20) and ALDOF (168 +/- 13) compared to CTL (123 +/- 12) and CNEP (134 +/- 13). Heart damage (lesion scores - median and interquartile range) was 7.0 (5.5-8.0) in ALDO and was fully prevented in ALDOF (1.5; 1.0-2.0). Also, left ventricular collagen volume fraction (%) in ALDOF (2.9 +/- 0.5) was similar to CTL (2.9 +/- 0.5) and CNEP (3.4 +/- 0.4) and decreased compared to ALDO (5.1 +/- 1.6). Felodipine partially prevented kidney injury since the damage score for ALDOF (2.0; 2.0-3.0) was significantly decreased compared to ALDO (7.5; 4.0-10.5), although higher than CTL (null score). Felodipine has a protective effect on the myocardium and kidney as evidenced by decreased perivascular inflammation, myocardial necrosis and fibrosis.