Vasorelaxation effects of homoisoflavonoids from Caesalpinia sappan in rat thoracic aortic rings.
- Author:
Wenjun HE
1
;
Taihui FANG
;
Ke ZHANG
;
Pengfei TU
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Aorta, Thoracic; drug effects; physiology; Caesalpinia; chemistry; Endothelium; metabolism; Enzyme Inhibitors; pharmacology; Flavonoids; chemistry; pharmacology; Guanylate Cyclase; antagonists & inhibitors; Male; Muscle Contraction; drug effects; NG-Nitroarginine Methyl Ester; pharmacology; Nitric Oxide Synthase Type III; antagonists & inhibitors; Phenylephrine; pharmacology; Potassium Chloride; pharmacology; Rats; Receptors, Cytoplasmic and Nuclear; antagonists & inhibitors; Soluble Guanylyl Cyclase; Vasodilation; drug effects; Vasodilator Agents; chemistry; pharmacology
- From: China Journal of Chinese Materia Medica 2009;34(6):731-734
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVETo identify and elucidate the vasorelaxant activity of homoisoflavonoids, the main chemical components from Lignum Sappan (the stems of Caesalpinia sappan), in isolated rat thoracic aortic rings pre-contracted with phenylephrine (PE, 1 micromol x L(-1)) and KCl (60 mmol x L(-1)).
METHODThe tension of rat thoracic aorta rings was used to evaluated the vasorelaxant activities of four homoisoflavonoids, brazlin (1), (E)-3-(3,4-dihydroxybenzylidene)-7-hydroxychroman-4-one (2), sappanone B (3), 3-deoxysappanone B (4).
RESULTCumulative addition of homoisoflavonoids (2, 3 and 4) (50-1000 micromol x L(-1)) exhibited an acute relaxation either in endothelium-intact or endothelium-denuded rings in a concentration-dependent manner. However, this relaxation was significantly inhibited in endothelium-denuded condition and in the presence of endothelial nitric oxide synthase (eNOS) inhibitor, N(W)-nitro-L-arginine methyl ester (L-NNA, 100 micromol x L(-1)), and a soluble guanylate cylcase (sGC) inhibitor, methylene blue (MB, 10 micromol x L(-1)) when addition of variation homoisoflavonoids brazlin (1) (50-1000 micromol x L(-1)).
CONCLUSIONThese results indicate that normo-homoisoflavonoids (2, 3 and 4) from Caesalpinia sappan mediates endothelium-independent vasodilator action in rat thoracic aortic rings, while the variation homoisoflavonoids brazlin elicits endothelium-dependent relaxation might via nitric oxide (NO)-cGMP pathway. This research could explain the pharmacological activities of homoisoflavonoids to a certain degree.
