The Effect of Sargassum angustifolium Ethanol Extract on Cadmium Chloride-Induced Hypertension in Rat

Background and objectives: Sargassum angustifolium is a brown alga in southwestern coastline of Persian Gulf. Regarding the presence of various bioactive compounds and evidence of antihypertensive effects in other species of Sargassum, we evaluated the effect of S. angustifolium ethanol extract in CdCl2-induced hypertension in Wistar rats. Methods: Alga extract was prepared by maceration method using 70% ethanol and assessed for total phenolics and salt content. CdCl2 (1.5 mg/kg/day) was administered intraperitoneally to the rats for two weeks. Treatment groups received S. angustifolium extract (20, 40 and 80 mg/kg) or nifedipine (10 mg/kg) orally and simultaneously were given CdCl2 for two weeks. Systolic blood pressure (SBP) and heart rate were measured using tail-cuff method. Total antioxidant capacity, urea, creatinine, electrolytesincluding sodium, potassium, calcium and chloride were estimated in blood samples. The weight and histopathology of kidney tissues were also evaluated. Results: The content of total phenolic as gallic acid equivalent and the salt as NaCl was 67.42 ± 9.5 mg/g and 6.9 g/100 g in dried ethanol extract, respectively. CdCl2 caused significant increase in SBP, kidney/body weight ratio, serum sodium and urea level and decrease in plasma total antioxidant capacity, and also histopathological alterations in kidney tissues. Treatment with S. angustifolium extract at the doses of 40 and 80 mg/kg significantly reversed hypertension and improved kidney weight, urea level and electrolyte changes, and enhanced antioxidant capacity and preventedhistopathological changes of kidney. Conclusion: Findings of the present study indicated antihypertensive and antioxidant effects of S. angustifolium extract against CdCl2-induced hypertension in rats.