The Effect of Angeli's salt on Acute Hemolysis in a Canine Model

安吉利盐对犬模型急性溶血的影响

• 批准号: 7733614
• 负责人: Charles Natanson
• 金额: $ 11.34万
• 依托单位: CLINICAL CENTER
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7733614
• 关键词: Acute; Adverse effects; Angeli' s salt; Animals; Atherosclerosis; Binding; Biochemical; Blood Circulation; Blood flow; Canis familiaris; Cardiac; Cell membrane; Cells; Cessation of life; Characteristics; Chemicals; Consumption; Creatinine clearance measurement; Equilibrium; Erythrocytes; Gastrointestinal tract structure; Goals; Hand; Health; Heart; Hemoglobin; Hemolysis; High Blood Pressure; Human; Hypertension; Inflammation; Infusion procedures; Injury; Intravenous; Kidney; Laboratories; Measures; Methemoglobin; Modeling; Nitric Oxide; Nitrites; Organ; Oxyhemoglobin; Peripheral; Peripheral Resistance; Physiological; Plasma; Protocols documentation; Rate; Recycling; Renal function; Risk; Role; System; Testing; Therapeutic; Toxic effect; Vascular Endothelium; Vasodilator Agents; Water; Whole Blood; hemodynamics; indexing; inhaled nitric oxide; iron nitrosyl; nitrosyl hemoglobin; pressure; prevent; response; vasoconstriction

The primary goal of this study is to determine the role of each component of whole blood (hemoglobin, stroma, hemoglobin + stroma) in the hypertension observed during hemolysis and then evaluate the therapeutic value of Angeli's salt (Na2N2O32-) in a canine model of acute intravascular hemolysis. Nitric oxide (NO) is a vasodilator which is constantly produced by the vascular endothelium. The amount of NO available in the circulation is, in part, regulated by the binding of NO to hemoglobin. Hemoglobin is normally contained within the red blood cell and reacts with nitric oxide at a relatively slow rate. However, the destruction of red blood cells within the circulation (intravascular hemolysis) causes the release of hemoglobin (cell-free hemoglobinh) from the red blood cell into the circulation. The cell-free hemoglobin released into the circulation during hemolysis binds to NO at a much faster rate than hemoglobin within the red blood cell. This binding of NO by cell-free hemoglobin disrupts the normal balance of NO available within the circulation resulting in vasoconstriction that decreases blood flow and leads to organ injury. Though it is not clear what role stroma (the contents of the red cell + the red cell membrane) has during hemolysis. This study will determine this role. In addition, Angeli's salt is known to react rapidly with hemoglobin to form, nitrosyl hemoglobin Fe(II)NO which does not bind NO. N2O3- (Angeli's Salt) NO2- + NO NO + Fe(II)-O2 (oxyhemoglobin in plasma) Fe(III) (methemoglobin) + Fe(III) + NO- Fe(II)-NO (iron-nitrosyl-hemoglobin) If the Angeli's salt can prevent the cell-free hemoglobin from binding NO, it may prevent the vasoconstriction and resulting organ injury that occurs during hemolysis. This study will test the ability of Angeli's salt to prevent cell-free hemoglobin binding of NO during hemolysis using the canine model of intravascular hemolysis that we successfully developed and used in two previous protocols. Our model uses a free water infusion to create intravascular hemolysis which mimics the physiologic and biochemical characteristics of acute intravascular hemolysis in the human. This model disrupts the red cell membrane within the circulation leading to the release of hemoglobin into circulation of the animal. In our model, acute intravascular hemolysis leads to changes in hemodynamics and organ function, i.e., increases in mean arterial pressure and systemic vascular resistance and decreases in heart and kidney function as measured by cardiac index and creatinine clearance respectively. Previous studies in our laboratory showed that elevated levels of cell-free hemoglobin consume NO, and therapy with inhaled nitric oxide or intravenous nitrite can limit the deleterious effects of intravascular hemolysis. Despite the demonstrated benefits, these two therapies have limitations. Inhaled nitric oxide is expensive, requires a specialized delivery system and is not readily available. Intravenous nitrite, although inexpensive and easy to administer, reacts slowly with cell free hemoglobin. Both therapies produce methemoglobin which: (1) promotes inflammation, (2) is associated with atherosclerosis and (3) can potentially undergo reduction and be recycled to free hemoglobin. Angeli's salt, on the other hand, has been shown to rapidly react with hemoglobin to produce nitrosyl hemoglobin. Unlike methemoglobin, (the product of nitrite or NO reacting with hemoglobin), nitrosyl hemoglobin is relatively stable and with no known toxicities. Angeli's salt also has the advantage of being inexpensive and can be administered intravenously. Thus, the chemical profile of Angeli's salt suggests that it should irreversibly react with cell free hemoglobin thereby preventing the consumption of NO, possibly reverse the adverse effects of intravascular hemolysis and have fewer side effects than either nitric oxide or nitrite therapy.

这项研究的主要目的是确定全血（血红蛋白，基质，血红蛋白 +基质）在溶血期间观察到的高血压中的每个成分的作用，然后评估急性血管内血解性血液解体犬模型中Angeli盐（NA2N2O32-）的治疗价值。一氧化氮（NO）是一种血管扩张剂，由血管内皮不断产生。循环中没有可用的量部分由NO与血红蛋白的结合所调节。血红蛋白通常包含在红细胞内，并以相对较慢的速率与一氧化氮反应。然而，循环中红细胞的破坏（血管内溶血）导致血红蛋白（无细胞血红蛋白）从红细胞释放到循环中。 溶血期间释放到循环中的无细胞血红蛋白的结合速度比红细胞内的血红蛋白快得多。 通过无细胞血红蛋白的NO结合破坏了循环中NO的正常平衡，导致血管收缩减少血液流动并导致器官损伤。 尽管尚不清楚基质（红细胞 +红细胞膜的含量）在溶血中具有什么作用。这项研究将决定这一角色。此外，已知Angeli的盐与血红蛋白迅速反应形成，硝基血红蛋白Fe（II）不结合NO。 N2O3-（Angeli's Salt）No2- +否 NO + Fe（II）-O2（等离子体中的Oxyhehemoglobin）Fe（iii）（甲基血红蛋白） + Fe（III） + NO- FE（II）-NO（硝基 - 血红蛋白铁） 如果Angeli的盐可以防止无细胞的血红蛋白结合NO，则可以防止血管收缩和导致的器官损伤在溶血期间发生。这项研究将测试Angeli盐使用血管内溶血的犬模型在溶血过程中预防无细胞血红蛋白结合的能力，我们成功地开发并使用了两种先前的方案。我们的模型使用自由水输注来创建血管内溶血，从而模仿人类急性血管内溶血的生理和生化特征。 该模型破坏了循环中的红细胞膜，导致血红蛋白释放到动物的循环中。在我们的模型中，急性血管内溶血会导致血液动力学和器官功能的变化，即平均动脉压和全身血管抗性的增加，并分别通过心脏指数和肌酐清除率衡量心脏和肾功能。 我们实验室中先前的研究表明，无细胞血红蛋白消耗的水平升高，对一氧化氮或静脉一氧化硝酸盐的治疗可能会限制血管内溶血的有害作用。 尽管有证明的好处，但这两种疗法仍有局限性。 吸入一氧化氮很昂贵，需要一个专门的输送系统，并且不容易获得。 静脉注射亚硝酸盐虽然廉价且易于施用，但与无细胞的血红蛋白反应缓慢。 两种疗法都产生高铁血红蛋白：（1）促进炎症，（2）与动脉粥样硬化有关，（3）可能会减少并回收自由血红蛋白。 另一方面，Angeli的盐已被证明与血红蛋白快速反应以产生硝基血红蛋白。 与非生物球蛋白（亚硝酸盐的产物或与血红蛋白反应的产物）不同，亚硝基血红蛋白相对稳定，没有已知的毒性。 Angeli的盐也具有便宜的优势，可以静脉注射。 因此，安吉利盐的化学特征表明，它应该与无细胞的无细胞血红蛋白反应，从而防止消耗NO，可能会逆转血管内溶血的不良影响，并且副作用比一氧化氮或硝酸盐治疗更少。