Effects of Standardized Aqueous Ethanolic Extract of Leaves of Ficus Deltoidea var. Trengganuensis on Blood Pressure in Spontaneously Hypertensive Rats

Abstract

Background: Laboratory evidence pertaining to the antihypertensive activity of a number of Ficus deltoidea (FD) varieties remains undetermined, although extracts of some of these varieties have been shown to have angiotensin-converting enzyme (ACE) inhibitory activity in vitro. Objective: This study, therefore, evaluated the effect of a standardized aqueous-ethanolic extract of leaves of Ficus deltoidea var. trengganuensis (FDT) on blood pressure in spontaneously hypertensive rats (SHR). Methods: SHR were given either to 800, 1000 or 1200 mg kg-1 body weight of standardized aqueous- ethanolic extract of FDT or 10 mg kg-1 body weight of losartan or 0.5 ml of distilled water daily for four weeks. Results: SBP decreased significantly in FDT- and losartan-treated rats (p < 0.05). Components of RAAS and other serum and urinary parameters were not different between the groups except for Endothelin-1, which was significantly lower than that in the controls. Urinary calcium excretion was significantly higher in FDT-treated rats (p < 0.05). Conclusion: It seems that daily oral administration of FDT significantly lowers blood pressure in SHR through mechanisms that do not involve RAAS but may involve the endothelium or other yetto- be-determined mechanisms.