PEROXYLIPIDS/NITRIC OXIDE IN THROMBOTIC STROKE

这项提议的广泛目标是证明抵押品 实验性大脑中动脉血栓性卒中的血管反应 大鼠大脑中动脉(MCA)区域可通过刺激或 抑制内皮源性松弛因子(EDRF)的合成。如果 这一断言是正确的，大脑中动脉区域梗塞的体积应该是 如果EDRF合成被抑制，则最大和一致(特定目标1)， 如果增强了EDRF合成，则最小化(但可能不一致) (具体目标2)。在正常井中观察梗塞的稠度- 抵押但不结扎颈动脉(Wistar)的大鼠 这是史无前例的，对抗缺血药物的评估也很重要。 通过观察EDRF刺激对心肌梗死的缓解作用，可以发现 EDRF诱导的侧支循环激活在临床上应用 缩小脑梗塞体积，即使大脑中动脉(或其他颅内动脉) 仍然被遮挡着。在特定的目标3中，梗死体积和一致性将 在最初受到EDRF抑制和MCA的大鼠中进行监测 完全恢复后血栓形成(持续时间长达3小时) 溶栓结合EDRF治疗大脑中动脉顺行血流 增强功能。然而，在这些明显最佳的回流条件下， 再灌注损伤的理论可能性也应最大化。 这一悖论将通过组织病理学和生化方法进行评估(见 过氧化脂质共轭双烯的术语) 前两个也(具体目标4)，从而便于评估长期- (可能)氧自由基介导的脂质的假设贡献 过氧化作用启动再灌流损伤。 在我们的方法中，大脑中动脉血栓是在特定的动脉段形成的 对光化学诱导的内皮细胞损伤的反应 静脉注射染料与聚焦的激光联合 合适的波长。对孟加拉玫瑰的反应形成血栓 用562 nm的Ar/Dy激光束注入和照射可以 由氯化血红素裂解(取自水蛭Haementeria ghilianii)抑制 EDRF的合成是通过静脉输注NG-硝基-1-精氨酸来实现的 盐酸甲酯(1-NAME)，而促进EDRF合成是 通过输注1-精氨酸盐酸盐(ARG)或 N(α)-苯甲酰基-L-精氨酸乙酯盐酸盐。共轭的 用分光光度法分析了黄连总脂提取物中的二烯含量。 小量(不到1毫克)皮质针活检。在……条件下 目的3及时检测再灌注期的脂质过氧化反应 与之前的努力相比，要更加始终如一。

The broad objective of this proposal is to demonstrate that the collateral vascular response to experimental thrombotic stroke of the middle cerebral artery (MCA) territory in the rat can be controlled by stimulating or inhibiting the synthesis of endothelial-derived relaxing factor (EDRF). If this assertion is correct, the volume of MCA territory infarct should be maximal and consistent if EDRF synthesis is suppressed (specific aim 1), and minimized (but likely inconsistent) if EDRF synthesis is enhanced (specific aim 2). Observation of infarct consistency in a normally well- collateralized but not carotid artery-ligated (Wistar) rat would be unprecedented, and important for evaluation of anti-ischemic drugs. Observation of infarct mitigation by EDRF stimulation would suggest that EDRF-induced activation of collateral circulation be used clinically to reduce infarct volume, even if the MCA (or other intracranial artery) remains occluded. In specific aim 3, infarct volume and consistency will be monitored in rats initially subjected to EDRF inhibition and MCA thrombosis (for time periods of up to 3 hours) after complete restoration of anterograde flow by lysis of the MCA thrombi together with EDRF enhancement. Under these apparently optimal reflow conditions, however, the theoretical possibility of reperfusion injury should also be maximized. This paradox will be evaluated histopathologically and biochemically (in terms of peroxidized lipid conjugated dienes) for this aim, and for the first two also (specific aim 4), thus facilitating assessment of the long- hypothesized contribution of (presumably) oxygen radical-mediated lipid peroxidation to the initiation of reperfusion injury. In our methodology the MCA thrombi are formed in specific arterial segments in response to photochemically induced endothelial injury mediated by an intravenously injected dye in conjunction with a focussed laser beam of the appropriate wavelength. Thrombi formed in response to rose bengal injection and irradiation with an argon/dye laser beam at 562 nm can be lysed by hementin (from the leech Haementeria ghilianii). Inhibition of EDRF synthesis is achieved by intravenous infusion of NG-nitro-1-arginine methyl ester hydrochloride (1-NAME), while enhancement of EDRF synthesis is achieved with infusion of either 1-arginine hydrochloride (ARG) or N(alpha)-benzoyl-l-arginine ethyl ester hydrochloride (BAEE). Conjugated diene content is analyzed spectroscopically in total lipid extracts from small (less than 1 mg) cortical punch biopsies. Under the conditions of aim 3 the detection of lipid peroxidation in time during reperfusion should be much more consistent compared to previous efforts.