The antiischemic properties of the flavonoids acetylvitexin-rhamnoside (AVR) and luteolin-7-glucoside-(LUT), combining phosphodiesterase (PDE)-inhibitory and antioxidant properties, were studied in comparison to amrinone (AMR) or superoxide dismutase (SOD). The effects of the new dihydropyridine-type calcium-agonist Bay T 5006 were studied in comparison to Bay K 8644. 2. In isolated Langendorff-rabbit hearts perfused at constant pressure, acute regional ischemia (MI) was induced by coronary artery occlusion (CAO) and quantitated from epicardial NADH-fluorescence photography. Drugs were applied either before or after CAO (pre-treatment or treatment) to permit distinguishing the influence of functional and direct cytoprotective actions in the poorly collateralized rabbit hearts. 3. SOD did not affect left ventricular pressure (LVP) or coronary flow (CF) and reduced MI only if applied before CAO. LVP and CF were enhanced by LUT or AMR but not by AVR. MI was reduced to a similar extent in hearts treated with either drug. Cardioprotection by LUT was not improved by starting drug application before CAO. 4. Bay K 8644 reduced LVP and particularly CF, whereas Bay T 5006 did not affect functional parameters. MI was enlarged by Bay K 8644 and remained unaffected by treatment or pretreatment with Bay T 5006. 5. AMR, LUT and AVR possess antiischemic properties related to an improvement of myocardial perfusion. Although oxygen free radicals contribute to ischemic tissue injury, as shown by the cardioprotective effectiveness of SOD, antioxidant properties of the flavonoids LUT and AVR do not seem to be relevant for the antiischemic effects. Our findings also give no evidence for antioxidant properties of dihydropyridines relevant for cardioprotection.
摘要
研究了具有磷酸二酯酶（PDE）抑制和抗氧化特性的黄酮类化合物乙酰基牡荆素鼠李糖苷（AVR）和木犀草素-7-葡萄糖苷（LUT）的抗缺血特性，并与氨力农（AMR）或超氧化物歧化酶（SOD）进行比较。还研究了新型二氢吡啶类钙激动剂Bay T 5006与Bay K 8644相比的作用。2. 在恒压灌注的离体Langendorff兔心脏中，通过冠状动脉闭塞（CAO）诱导急性局部缺血（MI），并通过心外膜NADH荧光摄影进行定量。在CAO之前或之后（预处理或治疗）应用药物，以区分在侧支循环不良的兔心脏中功能和直接细胞保护作用的影响。3. SOD不影响左心室压力（LVP）或冠状动脉流量（CF），仅在CAO之前应用时才降低MI。LUT或AMR可提高LVP和CF，但AVR则不能。用这两种药物治疗的心脏中MI均有类似程度的降低。在CAO之前开始应用LUT并不能增强其心脏保护作用。4. Bay K 8644降低LVP，尤其是CF，而Bay T 5006不影响功能参数。Bay K 8644使MI增大，而Bay T 5006治疗或预处理对MI无影响。5. AMR、LUT和AVR具有与改善心肌灌注相关的抗缺血特性。尽管氧自由基会导致缺血性组织损伤，如SOD的心脏保护作用所示，但黄酮类化合物LUT和AVR的抗氧化特性似乎与抗缺血作用无关。我们的研究结果也没有证据表明二氢吡啶类化合物的抗氧化特性与心脏保护有关。
