Vascular effect of extract from mulberry leaves and underlying mechanism.
- Author:
Man-Li XIA
1
;
Qin GAO
;
Xin-Mei ZHOU
;
Ling-Bo QIAN
;
Zhong-Hua SHEN
;
Hui-di JIANG
;
Qiang XIA
Author Information
- Publication Type:Journal Article
- MeSH: Acetates; isolation & purification; pharmacology; Animals; Aorta, Thoracic; drug effects; physiology; Dose-Response Relationship, Drug; In Vitro Techniques; Male; Morus; chemistry; Plant Extracts; isolation & purification; pharmacology; Plant Leaves; chemistry; Potassium; pharmacology; Rats; Rats, Sprague-Dawley; Ryanodine Receptor Calcium Release Channel; physiology; Vasoconstriction; drug effects; Vasodilation; drug effects
- From: Journal of Zhejiang University. Medical sciences 2007;36(1):48-53
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo investigate the vascular activity of extract from mulberry leaves (EML) on rat thoracic aorta and the underlying mechanism.
METHODSIsolated thoracic rings of Sprague-Dawley rats were mounted on the organ bath and the tension of the vessel was recorded.
RESULT(1) EML produced a concentration-dependent vasorelaxation of aorta preconstricted by high K(+) (60 mmol/L) or 10(-6) mol/L phenylephrine (PE) in endothelium-intact and endothelium-denuded arteries. (2) EML at EC(50) concentration reduced the calcium dose-response curve. (3) After incubation of aorta with verapamil, EML induced vasocontraction of aorta preconstricted by PE, which was abolished by ruthenium red.
CONCLUSIONThe vascular effect of EML is biphasic, the vasorelaxation is greater than the vasocontraction. The vasorelaxation induced by EML may be mediated by inhibition of voltage-and receptor-dependent calcium channels in vascular smooth muscle cells, while the vasocontraction is via activation of ryanodine receptor in endoplasmic reticulum.
