کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2546318 1560409 2008 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Endothelium-independent relaxation and contraction of rat aorta induced by ethyl acetate extract from leaves of Morus alba (L.)
موضوعات مرتبط
علوم پزشکی و سلامت داروسازی، سم شناسی و علوم دارویی داروشناسی
پیش نمایش صفحه اول مقاله
Endothelium-independent relaxation and contraction of rat aorta induced by ethyl acetate extract from leaves of Morus alba (L.)
چکیده انگلیسی

Aim of the studyBased on screening for vasoactive traditional Chinese medicinal herbs, the present study was performed to investigate the vasoactive effects of an ethyl acetate extract from leaves of Morus alba (L.) (ELM) on rat thoracic aorta and the mechanisms underlying these effects.Materials and methodsIsolated rat thoracic rings were mounted in an organ bath system and the effects of ELM on their responses were evaluated.ResultsELM (0.125–32.000 g/l) induced a concentration-dependent relaxation (P < 0.01 vs. control) both in endothelium-intact and -denuded aortas precontracted by high K+ (6 × 10−2 M) or 10−6 M phenylephrine (PE). In endothelium-denuded aortas, ELM at the EC50 concentration reduced Ca2+-induced contraction (P < 0.01 vs. control) after PE or KCl had generated a stable contraction in Ca2+-free solution. And after incubation with verapamil, ELM induced contraction in endothelium-denuded aortas precontracted by PE (P < 0.01 vs. control); this was abolished by ruthenium red (P < 0.01 vs. ELM-treated endothelium-denuded group; P > 0.05 vs. control), but not by heparin (P > 0.01 vs. ELM-treated endothelium-denuded group; P < 0.01 vs. control).ConclusionsThe results showed that ELM had dual vasoactive effects, and the relaxation was greater than the contraction. The relaxation was mediated by inhibition of voltage- and receptor-dependent Ca2+ channels in vascular smooth muscle cells, while the contraction occurred via activation of ryanodine receptors in the sarcoplasmic reticulum.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Ethnopharmacology - Volume 120, Issue 3, 8 December 2008, Pages 442–446
نویسندگان
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