CEREBAL ARTERIAL ADVENTITIA AND VASOSPASM

大脑动脉外膜和血管痉挛

• 批准号: 2760454
• 负责人: Zvonimir S Katusic
• 金额: $ 25.98万
• 依托单位: MAYO CLINIC ROCHESTER
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-01-01 至 2001-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2760454
• 关键词: cellular pathology; cerebral artery; cerebrovascular disorders; connective tissue; dogs; endothelin; enzyme activity; gene therapy; immunocytochemistry; nitric oxide; nitric oxide synthase; nonhuman therapy evaluation; radioimmunoassay; recombinant proteins; transfection; vasomotion; vasospasm

Chronic cerebral vasospasm is a major cause of morbidity and mortality in patients with subarachnoid hemorrhage. Pathogenesis of vasospasm is not completely understood, but existing evidence suggests that impairment of nitric oxide vasodilator function is an important mechanism underlying narrowing of arteries exposed to autologous blood. We hypothesize that increased biosynthesis of nitric oxide in adventitia of cerebral arteries may cause vasodilatation and prevent development of vasospasm. To test this hypothesis, we over-expressed recombinant endothelial nitric oxide synthase (eNOS) gene in adventitial fibroblasts of cerebral arteries by adenoviral-mediated gene transfer. This model provides unique opportunity to characterize the effects of nitric oxide released from adventitia on regulation of vasomotor reactivity, as well as signal transduction pathways coupled to activation of recombinant eNOS protein. For instance, preliminary findings indicate that in our model, vasoconstrictor effect of a putative mediator of vasospasm, endothelin-1, is reversed to vasodilatation. This reversal is apparently due to endothelin-1-induced activation of recombinant eNOS protein expressed in adventitia. We propose to study expression and function of recombinant eNOS gene in adventitia of cerebral arteries by immunohistochemistry,. measurements of eNOS enzymatic activity, radioimmunoassay of cyclic GMP and in vitro and in vivo analysis of vasomotor reactivity of tansduced arteries."Double hemorrhage" canine model of cerebral vasospasm will be used to study effects of the recombinant eNOS gene on vascular tone of spastic arteries. We anticipate that experiments propose in this application will determine whether eNOS over-expression in the adventitia can serve as a substitute source of nitric oxide, and whether this approach can be used to restore nitric oxide biosynthesis in cerebral arterial wall. Our studies will also expand the knowledge base concerning the vascular biology of adventitia, and its role as a target for transfer and expression of therapeutically beneficial recombinant proteins.

慢性大脑血管痉挛是发病率和死亡率的主要原因 蛛网膜下腔出血的患者。血管痉挛的发病机理是 尚未完全理解，但现有证据表明 一氧化氮血管扩张剂功能是重要的 暴露于自体血的动脉狭窄的机制。 我们假设增加了氧化氮的生物合成增加 大脑动脉可能导致血管舒张并防止发育 血管痉挛。 为了检验这一假设，我们过表达重组 内皮一氧化氮合酶（ENOS）基因在外膜成纤维细胞中 腺病毒介导的基因转移的脑动脉。 这个模型 提供独特的机会来表征一氧化氮的影响 也从Addeditia发行了有关血管舒缩反应性的调节 作为信号转导途径，与重组激活相连 eNOS蛋白。 例如，初步发现表明在我们的 模型，血管痉挛介质的血管收缩效应， 内皮素-1被逆转到血管舒张。 这种逆转是 显然是由于内皮素1诱导的重组eNOS激活 蛋白质在Addeditia中表达。我们建议研究表达和 通过 免疫组织化学，。测量eNOS酶活性， 循环GMP的放射免疫分子和体外和体内分析 诱导动脉的血管舒缩反应性。“双出血”犬 脑血管痉挛的模型将用于研究 重组eNOS基因在痉挛性动脉的血管张力上。 我们 预计本应用程序中提出的实验将确定 eNos是否在Addeditia中的过表达可以用作替代品 一氧化氮的来源，以及是否可以使用这种方法来恢复 一氧化氮在脑动脉壁中的生物合成。 我们的研究将 还扩大有关血管生物学的知识基础 Adventitia及其作为转移和表达的目标的作用 治疗上有益的重组蛋白。