@article{oai:toyama.repo.nii.ac.jp:00002220, author = {Tanikawa, Kiyoaki and Goto, Hirozo and Nakamura, Norio and Tanaka, Nobumitsu and Hattori, Masao and Itoh, Takashi and Terasawa, Katsutoshi}, issue = {2}, journal = {和漢医薬学雑誌 = Journal of traditional medicines}, month = {Jul}, note = {application/pdf, Cinnamonomi Cortex (the bark of Cinnamomum cassia BLUME) is a crude drug that is widely used in spices and medical products. Although improvement of blood flow by this plant component has long been known, there have been no reports concerning the mechanism involved. We studied the vasodilator actions of this drug especially focusing on the role of endothelium in the isolated vascular bed. Tannin from Cinnamonomi Cortex (TCC) relaxed prostaglandin F_<2α>-precontracted ring preparations of rat aorta with intact endothelium. TCC did not cause relaxation of specimens without endothelium, and TCC-induced relaxation was inhibited by pretreatment with 10^<-4>M N^G-nitro-l-arginine methyl ester. Dimer, trimer, tetramer, and pentamer components of TCC also produced endothelium-dependent vasodilatation. Stronger relaxation was caused by higher molecular weight tannins, and endothelium-dependent vasodilation even appeared at low concentrations. In conclusion, we found that TCC exhibits an endothelium-dependent vasodilatation in the isolated rat aorta mainly via endothelium derived NO. NO mediated endothelium-dependent relaxation seems to be more potent for TCC with higher molecular weight than that with lower molecular weight. 桂皮の血流改善作用については古くから知られており,これに関連した報告はあるものの,その詳細な検討はなされていない。今回我々はマグヌス法を用いて,ラット胸部大動脈輪状標本における桂皮含有クンニンの血管作動性について検討した。桂皮含有タンニンは,プロスタグランディンF_<2α>(PGF_<2α>)の血管収縮に対し,内皮保存血管において濃度依存性に血管弛緩作用が認められた。しかし,内皮除去血管及ぴN^G-nitro-l-argininemethyl ester(L-NAME)前処置内皮保存血管においては,血管弛緩作用はほぼ消失した。以上より,桂皮含有タンニンの血管弛緩作用は内皮依存性であることが明らかとなった。桂皮含有タンニンをさらに二量体から五量体までのタンニン画分に分取し検討したところ,二量体以上の重合したタンニンにおいて血管弛緩作用が認められた。また,重合度が増すに従い血管弛緩作用はより低い濃度で発揮され,作用も増強されることが明らかとなった。, Article}, pages = {45--50}, title = {Endothelium-dependent vasodilator effect of tannin extract from Cinnamonomi Cortex on isolated rat aorta}, volume = {16}, year = {1999} }