ID | 111318 |
著者 |
Yin, Hua
The University of Tokushima
|
キーワード | L-DOPA
aortic rings
nitric oxide
vasorelaxation
reactive oxygen species
|
資料タイプ |
学術雑誌論文
|
抄録 | Objectives : To clarify the underlying mechanisms of L-DOPA induced vasoconstriction in rat aorta. Methods : The effect of L-DOPA on phenylephrine-induced contractile force of blood vessels was examined in vitro using rat aortic ring preparations by isometric tension experiment. Involvement of nitric oxide (NO) in the effect of L-DOPA on vascular smooth muscle was studied by using Nω-Nitro-L-arginine (L-NNA), Sodium nitroprusside (SNP) in endothelium-intact and endothelium-denuded aortic rings. Results : L-DOPA potentiated α-adrenergic receptor- and depolarization-induced vascular contraction and inhibited acetylcholine-induced vasorelaxation. This effect was diminished by pretreatment of the aortic rings with L-NNA, an inhibitor of NO synthesis, or by removing the endothelium from the ring preparations. In endothelium-denuded rings, L-DOPA inhibited exogenous NO-dependent but not cGMP-mediated vasorelaxation. Increases in cGMP levels in response to an NO donor were attenuated by L-DOPA in cultured rat aortic smooth muscle cells. L-DOPA could not contract rings (without endothelium) pretreated with 3-(5’-hydroxymethyl- 2’-furyl)-1-benzyl indazole (YC-1), an activator of guanylyl cyclase, but SOD (150 U/ml) pretreatment of rings with endothelium inhibited contraction by L-DOPA. Conclusions : These results suggest that L-DOPA inhibits nitric-dependent vasorelaxation on vascular smooth muscle cells via production of reactive oxygen species.
|
掲載誌名 |
The Journal of Medical Investigation
|
ISSN | 13496867
13431420
|
cat書誌ID | AA11166929
AA12022913
|
出版者 | Faculty of Medicine Tokushima University
|
巻 | 56
|
号 | 3-4
|
開始ページ | 120
|
終了ページ | 129
|
並び順 | 120
|
発行日 | 2009-08
|
EDB ID | |
出版社版DOI | |
出版社版URL | |
フルテキストファイル | |
言語 |
eng
|
著者版フラグ |
出版社版
|
部局 |
医学系
|