The effects of paeonol on the electrophysiological properties of cardiac ventricular myocytes

Previous studies have shown that "Mudanpi", a Chinese herbal medicine, has a significant cardioprotective effect against myocardial ischaemia. Based on these findings we hypothesised that paeonol, the main component of Mudanpi, might have an effect on the cellular electrophysiology of cardiac ventricular myocytes. The effects of paeonol on the action potential and ion channels of cardiac ventricular myocytes were studied using the standard whole-cell configuration of the patch-clamp technique. Ventricular myocytes were isolated from the hearts of adult guinea-pig by enzymic dispersion. The myocytes were continuously perfused with various experimental solutions at room temperature and paeonol applied in the perfusate. Action potentials and membrane currents were recorded using both current and voltage clamp modes of the patch-clamp technique. Paeonol, at concentrations 160 mu M and 640 mu M, decreased the action potential upstroke phase, an action associated with the blockade of the voltage-gated, fast sodium channel. The effects of paeonol on both action potential and Na+ current were concentration dependent. Paeonol had a high affinity for inactivated sodium channels. Paeonol also shortened the action potential duration, in a manner not associated with the blockade of the calcium current, or the enhancement of potassium currents. These findings suggest that paeonol, and therefore Mudanpi, may possess antiarrhythmic activity, which may confer its cardioprotective effects. (c) 2006 Elsevier B.V All rights reserved.

中国药用牡丹资源评价

我国牡丹资源丰富、药用历史悠久，但长期以来，资源与药效关系不清严重阻碍着丹皮的产业化发展。建立一套综合评价体系，比较不同牡丹资源间的差异，科学评价、准确定位各地不同品种的利用价值，对稳定我国丹皮质量、可持续、集约化发展丹皮产业具有重要的意义。 本实验以我国丰富的药用牡丹资源为材料，从观赏和药用价值两方面首先探讨综合评价牡丹资源的体系。在观赏价值考察中重点比较了花型、花色、花期等性状;药用价值则从根的产量、重金属含量以及七种主要药效成分含量三方面来比较;重金属含量以原子分光光度法检测，药效成分则以高效液相色谱和质谱进行分离鉴定和定性、定量检测。利用建立的综合评价体系对野生种、各地药用品种进行了评价，对丹皮生产相关环节的问题进行了讨论，并初步探讨了药效成分的遗传规律。结果如下： 1、引种的野生牡丹药用价值不比栽培品种高，建议作为育种材料。 2、不同品种间药效成分含量存在显著差异，综合比较‘JSF’、‘CKL’、‘凤丹’适于药用栽培，‘赵粉’、‘朱砂垒’、‘首案红’等品种适宜观赏栽培，‘太平红’、‘JPH’等可花药兼用。 3、不同的土壤、气候环境对丹皮药效成分含量有明显的影响，丹皮中重金属含量主要与土壤环境关系密切。 4、根的粗细程度与药效成分含量关系不大，建议市场药材分级时充分考虑。 5、丹皮的药效成分含量与株龄、采收期、储藏时期关系密切;建议采收、应用根据各地的品种、气候条件及市场情况而定，在保证较高药效成分含量的前提下，尽量缩短生产、流通周期。 6、催花、嫁接对一些牡丹品种的药用价值影响不大，可合理开发利用。 7、药效成分的遗传有一定的规律，86%的子代丹皮酚含量高于父母本或亲本之一;丹皮酚原苷和没食子酰羟基芍药苷含量受父本影响较大，而芍药苷、苯甲酰芍药苷、丹皮酚新苷、没食子酰丹皮酚苷含量受母本影响较大。