The infusion of the desertic plant Nolana ramosissima I.M. Johnst showed vascular smooth muscle relaxation in rat aorta and the presence of several phenolic compounds, which were detected by high resolution UHPLC-Orbitrap-HESI-MS. In addition, five flavonoids were rapidly isolated from a methanolic extract using high-performance counter-current chromatography (HPCCC). The N. ramosissima extract showed endothelium-independent relaxation effect in rat aorta. Sixty-one compounds were detected in the infusion, mainly glycosylated flavonoids, flavanones and several oxylipins, suggesting that a synergistic effect between the compounds in the extracts could be responsible for the relaxation activity. Vascular activity experiments were done in isolated organ bath. In rat aorta, a nitric oxide inhibitor did not prevent the relaxation effects of the extract; however, a selective guanylyl cyclase inhibitor partially blunted this effect. The compound 5,3′-dihydroxy-4′7-dimethoxyflavone presented higher relaxation effect than 100 μg/mL of N. ramosissima extract. The extract and the isolated metabolites from N. ramosissima can show relaxation effects on rat aorta by a mechanism that is independent of the endothelium.

中文翻译：

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从地方性物种 Nolana ramosissima IM Johnst 中快速分离类黄酮及其对大鼠主动脉的内皮非依赖性松弛作用

荒漠植物 Nolana ramosissima IM Johnst 的输注显示大鼠主动脉血管平滑肌松弛，并且存在几种酚类化合物，通过高分辨率 UHPLC-Orbitrap-HESI-MS 检测到。此外，使用高效逆流色谱 (HPCCC) 从甲醇提取物中快速分离出五种黄酮类化合物。N. ramosissima 提取物在大鼠主动脉中显示出不依赖于内皮的松弛作用。在输液中检测到 61 种化合物，主要是糖基化的黄酮类化合物、黄烷酮和几种oxylipins，表明提取物中化合物之间的协同作用可能是造成松弛活性的原因。血管活性实验在离体器官浴中进行。在大鼠主动脉中，一氧化氮抑制剂不能阻止提取物的松弛作用；然而，选择性鸟苷酸环化酶抑制剂部分减弱了这种作用。化合物5,3'-二羟基-4'7-二甲氧基黄酮表现出比100 μg/mL N. ramosissima提取物更高的松弛效果。N. ramosissima 的提取物和分离的代谢物可以通过一种独立于内皮的机制显示对大鼠主动脉的松弛作用。