Effects of Chemical Components Obtained from Plants on the Aorta with Endothelium

丹参和牛膝来源于唇形科植物，在中药中被用作生药活血化瘀。我们寻找了两种药物对大鼠带血管内皮血管条的血管扩张作用：(1)丹参的干燥根含有石香酸(LSA和LSA-B)作为其化学成分。我们报道了LSA-B是一种内皮依赖性血管扩张剂，它通过对肠系膜动脉床等阻力动脉的内皮依赖性血管扩张而引起大鼠的降压作用。在我们对丹参有效成分的持续研究中，推测存在另一种有效的血管扩张剂，该成分似乎是该生药的未知成分。根据在此资助期间获得的化学和光谱结果，有效的血管扩张剂被鉴定为(2S，3S)-4-[(E)-2carboxy-ethenyl]-2-(3，4-dihydroxyphenyl)-2，3-二氢-7-羟基-3-苯并呋喃甲酸(De…更多的PL-LSA=8-表儿茶酸)，是由LSA和LSA-B通过碱性水解得到的。此外，Depl-LSA对去甲肾上腺素(NE)预收缩的大鼠主动脉条有持续缓慢的松弛作用。考虑到其他四种药理实验的结果，我们推测Depl-LSA可通过减少Ca~(2+)的动员来抑制去甲肾上腺素(NE)引起的血管条收缩。Depl-LSA可能用于高血压的治疗，因为这种药物抑制NE诱导的持续收缩。(2)由于商业上可获得的Takuran主要来自菊科植物紫茎泽兰的地上部分，我们于1994年培育了Lycopus Lucidus，以获得足够的收成来研究其血管扩张成分。经化学和层析分离得到3个具有血管扩张活性的化合物。它们中的任何一个似乎都是一种内皮非依赖性血管扩张剂。它们的鉴定、有效性和作用机制有待于进一步研究。较少

Tanjin and takuran originate from Labiatae plants, and have been used as crude drugs promoting blood circulation (ku-oketsu) in Chinese medicine. We searched thetwo drugs for vasodilating components to rat aortic strips with endothelium.(1) Tanjin, dried root of Salvia miltiorrhiza, contains lithospermic acids (LSA and LSA-B) as its chemical constituents. We reported that LSA-B is an endothelium-dependent vasodilator and that it induces hypotensive effects in rats through endothelium-dependent vasodilation of a resistance artery such as a mesenteric arterial bed.In our continuing research for active ingredients of tanjin, the presenceof another effective vasodilator was presumed, which seemed to be an unknown component of this crude drug. On the basis of chemical and spectral results obtained during the period of this grant-in aid, the effective vasodilator was identified as (2S, 3S)-4-[(E)-2carboxy-ethenyl]-2-(3,4-dihydroxyphenyl)-2, 3-dihydro-7-hydroxy-3-benzofurancarboxylic acid (de … More PL-LSA=8-epiblechnic acid), and was chemically derived from LSA and LSA-B by alkaline hydrolysis. In addition, dePL-LSA caused a sustained, slowly developing relaxation of rat aortic strips precontracted with norepinephrine (NE) in preparations with or without endothelium at a concentration 10^<-7>M.Taking into consideration the results of other four kinds of pharmacological experiments, we presume that dePL-LSA inhibits NE-induced contraction of the aortic strips through reduction in Ca^<2+> mobilization. DePL-LSA may be useful in the tretmanet of hypertension, because this agent inhibits NE-induced, sustained contraction.(2)Since commercially-available takuran mostly comes from upper-ground part of Eupatorium fortunei (Compositae), we cultivated Lycopus lucidus in 1994 to get a harvest enough to investigate its vasodilating components. Through the chemical and chromatographic separation of a water-extract from the plant material, three compounds were isolated, which showed vasodilating activities. Any of them seemed to be an endothelium-independent vasodilator. Identification, efficiency and mechanism of them should further be investigated. Less