- 作者：Esther Ngo Lemba Tom ; Corine Girard-Thernier ; H茅l猫ne Martin ; Th茅ophile Dimo ; Magalie Alvergnas ; Maude Nappey ; Alain Berthelot ; C茅line Demougeot
- 关键词：8-iso-PGF2伪 ; 8 isoprostaglandin F2伪 ; ACh ; acetylcholine ; CYP 3A ; cytochrome P 450 3A ; KCl ; potassium chloride ; l-NAME ; NW-nitro-l-arginine methyl ester ; NO ; nitric oxide ; NOS ; nitric oxide synthase ; PE ; phenylephrine ; SBP ; systolic blood pressure ; SHR ; spontaneously hypertensive rats ; SNP ; sodium nitroprusside ; TMSE ; Terminalia superba methylene chloride extract ; VSMCs ; vascular smooth muscle cells ; WKY ; Wistar Kyoto rats
- 刊名：Journal of Ethnopharmacology
- 出版年：10 January, 2014
- 年：2014
- 卷：151
- 期：1
- 页码：372-379
- 全文大小：486 K
Ethnopharmacological relevance
The stem bark of Terminalia superba (TS) is widely used as a decoction by Cameroonian folk medicine for the treatment of hypertension. The aim of the present study was to evaluate the effect of a chronic treatment with a TS extract on spontaneously hypertensive rats (SHR) with respect to efficacy, biochemical mechanisms and safety.Materials and methods
Eleven-week-old SHR and normotensive Wistar Kyoto rats (WKY) were daily treated by gavage with a methylene chloride extract of stem bark of Terminalia superba (TMSE, 150 mg/kg) or with the vehicle for 5 weeks. Systolic blood pressure (SBP) was measured weekly using the tail-cuff method. At the end of the treatment period, vascular function was assessed on isolated thoracic rings, urinary 8-iso-PGF2伪 levels were measured and cytochrome P-450 3A (CYP 3A) activity was evaluated in liver microsomes.
Results
TMSE reduced SBP (P<0.001) in SHR but not in WKY rats. In SHR, the vasorelaxant response to acetylcholine was significantly improved by TMSE as a result of increased nitric oxide synthase (NO) activity and decreased superoxide anion production. In addition, TMSE reduced the vasoconstrictive effect of phenylephrine and improved the sensitivity of smooth muscle cells to NO. TMSE dramatically decreased 8-iso-PGF2伪 levels in SHR. By contrast, TMSE did not affect all these parameters in WKY rats. Neither diuresis nor the hepatic CYP 3A activity was modified in both animal groups.
Conclusions
This study demonstrated that Terminalia superba has a potent antihypertensive activity in SHR which is partly due to endothelium-dependent and endothelium-independent effects as well as decreased oxidative stress. The data also provide evidence for the lack of herb-drug interaction through hepatic CYP 3A.