Department of Pharmacology, Tianjin Medical University, Tianjin 300070, China.
College of Pharmacy, Nankai University, Tianjin 300071, China.
Evid Based Complement Alternat Med. 2014;2014:707908. doi: 10.1155/2014/707908. Epub 2014 May 21.
Chinese people commonly make jasmine tea for recreation and health care. Actually, its medicinal value needs more exploration. In this study, vasorelaxant effect of ethanol extract of jasmine flower (EEJ) on isolated rat thoracic aorta rings was investigated and [Ca(2+)] was determined in vascular smooth muscle cells by laser scanning confocal microscope (LSCM). The result of aorta rings showed that EEJ could cause concentration-dependent relaxation of endothelium-intact rings precontracted with phenylephrine or KCl which was attenuated after preincubation of the rings with L-NAME and three different K(+) channel inhibitors; however, indomethacin and glibenclamide did not affect the vasodilatation of EEJ. In addition, EEJ could inhibit contraction induced by PE on endothelium-denuded rings in Ca(2+)-free medium as well as by accumulation of Ca(2+) in Ca(2+)-free medium with high K(+). LSCM also showed that EEJ could lower the elevated level of [Ca(2+)] induced by KCl. These indicate that the vasodilation of EEJ is in part related to causing the release of nitric oxide, activation of K(+) channels, inhibition of influx of excalcium, and release of calcium from sarcoplasmic reticulum. A total of 20 main ingredients, were identified in EEJ by UPLC-DAD/Q-TOF-MS. The vasodilation activity should be attributed to the high content of flavonoid glycosides and iridoid glycosides found in EEJ.
中国人通常将茉莉花茶作为一种娱乐和保健饮品。实际上，其药用价值还需要进一步探索。在本研究中，通过激光扫描共聚焦显微镜（LSCM）测定血管平滑肌细胞中的[Ca(2+)]，研究了茉莉花乙醇提取物（EEJ）对离体大鼠胸主动脉环的血管舒张作用。主动脉环的结果表明，EEJ 可引起预先用苯肾上腺素或 KCl 收缩的完整内皮环浓度依赖性舒张，该舒张作用在环预先用 L-NAME 和三种不同的 K(+)通道抑制剂孵育后被减弱；然而，吲哚美辛和格列本脲对 EEJ 的血管舒张作用没有影响。此外，EEJ 可抑制无内皮环中由 PE 引起的收缩，以及在无 Ca(2+)的高 K(+)介质中由 Ca(2+)积累引起的收缩。LSCM 还表明，EEJ 可降低 KCl 引起的[Ca(2+)]升高。这些表明 EEJ 的血管舒张作用部分与引起一氧化氮释放、激活 K(+)通道、抑制外钙内流以及肌浆网中钙释放有关。通过 UPLC-DAD/Q-TOF-MS 在 EEJ 中鉴定出 20 种主要成分。血管舒张活性应归因于 EEJ 中发现的类黄酮糖苷和裂环烯醚萜糖苷的高含量。
