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Background and Objectives: Syzygium gratum (SG) extract has antioxidant, anticancer and vascular protective activities. This study aimed to investigate the effect of SG extract on blood pressure and renal remodeling in Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME)-induced hypertensive rats.
Methods: Male Sprague-Dawley rats were administered with L-NAME (40 mg/kg/day) in drinking water for 5 weeks in order to induce hypertension. Hypertensive rats were treated with SG extract (300 mg/kg/day) or vehicle for the last 2 weeks. Systolic blood pressure and renal fibrosis were evaluated.
Results: Rats treated with L-NAME had high systolic blood pressure (187.8 ± 5.1 mmHg vs. 124.4 ± 2.8 mmHg) and increases in renal tubulointerstitial (3.8 ± 0.1 % vs. 2.1 ± 0.2 %) and corpuscular fibrosis (11.3 ± 1.1 % vs. 4.8 ± 0.4 %) compared with control rats (p<0.05). Treatment of hypertensive rats with SG extract significantly reduced systolic blood pressure (154.7 ± 2.7 mmHg), and alleviated renal tubulointerstitial and corpuscular fibrosis (2.4 ± 0.1 % and 5.5 ± 0.4 % respectively) (p<0.05).
Conclusion: Our results indicate that SG extract decreased blood pressure and alleviated renal fibrosis in L-NAME-induced hypertensive rats.
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