Effects of phenylpropanoid and iridoid glycosides on free radical-induced impairment of endothelium-dependent relaxation in rat aortic rings.
The protective effect of phenylpropanoid glycosides, forsythoside B and alyssonoside, and the iridoid glycoside lamiide, isolated from the aerial parts of Phlomis pungens var. pungens, against free radical-induced impairment of endothelium-dependent relaxation in isolated rat aorta was investigated. Aortic rings were exposed to free radicals by the electrolysis of the physiological bathing solution. Free radical-induced inhibition of the endothelium-dependent relaxation in response to acetylcholine was countered by incubation of the aortic rings before electrolysis with the aqueous extract (200 microg/ml), phenylpropanoid fraction (100 microg/ml) and iridoid fraction (150 microg/ml) of P. pungens var. pungens. Major components of the phenylpropanoid fraction forsythoside B and alyssonoside also prevented the inhibition of the acetylcholine response, at 10(-4) M concentration. However, the major component of iridoid fraction lamiide was found ineffective at the same concentration. The protective activity of phenylpropanoid glycosides against the free radical-induced impairment of endothelium-dependent relaxation may be related to their free radical scavenging property.
Ismailoglu
U B
UB
Department of Pharmacology, Faculty of Pharmacy, Hacettepe University, 06100, Ankara, Turkey.
Saracoglu
I
I
Harput
U S
US
Sahin-Erdemli
I
I
D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects* / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004353:Drug Evaluation, Preclinical; D004730:Endothelium, Vascular / Q000187:drug effects* / Q000502:physiology; D016166:Free Radical Scavengers / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D006027:Glycosides / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D019686:Lamiaceae / Q000737:chemistry; D008297:Male; D010626:Phenylethyl Alcohol / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D020005:Propanols / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D051381:Rats; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology
D016166:Free Radical Scavengers; D006027:Glycosides; D010936:Plant Extracts; D020005:Propanols; C439395:1-phenylpropanol; D010626:Phenylethyl Alcohol