Abstract
Background: This study evaluated the cardioprotective effect of spironolactone in Wistar rats subjected to 5/6 nephrectomy. Materials and Methods: Chronic kidney insufficiency was induced in Wistar rats via 5/6 nephrectomy. Animals were assigned to three groups: Group 1 — Chronic kidney insufficiency rats treated with spironolactone (0.2 mg/day), Group 2 — Chronic kidney insufficiency rats without treatment, and Group 3 — sham-operated controls. Before euthanasia, mean arterial pressure, heart rate, and 24-hour urine output were recorded. Plasma was analyzed for aldosterone, urea, creatinine, electrolytes, and total protein. The myocardial hypertrophy index was used to assess cardiac changes. Results: Heart rate did not differ significantly among groups. Mean arterial pressure was significantly higher in both Chronic kidney insufficiency groups than in controls (151.3 ± 2.7 mmHg in Group 1, 151.4 ± 2.3 mmHg in Group 2, vs. 121.15 ± 1.8 mmHg in controls, p<0.05). In Group 1, the myocardial hypertrophy index was similar to controls (2.52 ± 0.06 vs. 2.35 ± 0.09, p>0.05), whereas in Group 2 it was significantly greater (2.8 ± 0.11, p<0.05). Histological analysis revealed no arteriole wall thickening or connective tissue increase in Groups 1 and 3, while Group 2 showed pronounced arteriole wall thickening. Conclusion: Spironolactone-mediated aldosterone receptor blockade exerts a cardioprotective effect in Wistar rats with Chronic kidney insufficiency induced by 5/6 nephrectomy, independent of systemic Mean systemic arterial pressure changes.