CARBON MONOXIDE AND VASCULAR SMOOTH MUSCLE CELL FUNCTION

这项研究计划的广泛和长期目标是建立 血管平滑肌细胞（SMC）来源的一氧化碳（CO）作为一种新的 生物学上重要的信使分子， 血管壁损伤部位的内稳态。我们最近发现 SMC通过血红素加氧酶-1（HO-1）催化生成CO， 特定的体液和血液动力学因素在 血管损伤微环境诱导HO-1基因表达和CO release.基于这些发现，我们建议研究生物学 CO对血管平滑肌细胞功能的影响。这些研究将决定 外源性给予和内源性来源的CO对 血管张力、SMC增殖和SMC胶原合成。在所有 在CO被证明改变SMC功能的情况下，我们将确定 这种效应的分子基础。因为我们已经证明了一氧化碳刺激 可溶性鸟苷酸环化酶活性在血管平滑肌细胞，我们将研究 cGMP和蛋白激酶G（PKG）和/或A（PKA）是否介导了 我们将进一步探讨CO作为一种生物学效应的作用， SMC的自分泌调节剂通过产生过表达的SMC来发挥作用 HO-1酶。如果HO-1转染的SMC改变了生物学反应， 将尝试通过使用特定的 金属原卟啉HO抑制剂或用HO-1反义核酸治疗SMC 寡脱氧核苷酸 最后，我们将研究CO在 调节大鼠颈动脉内膜增厚和血管反应性 动脉球囊损伤模型。我们将确定当地是否 HO-1活性和CO产生抑制或过表达调节 损伤形成和血管损伤部位的血管张力。在 此外，我们将确定cGMP和PKG/PKA是否负责 CO的任何体内效应。预计这些研究 将（a）建立CO作为一种新的SMC衍生的信号分子， 调节SMC收缩、增殖和胶原合成，和（B） 导致新的治疗策略的发展， 闭塞性血管疾病

The broad, long-term objective of this research proposal is to establish vascular smooth muscle cell (SMC)-derived carbon monoxide (CO) as a novel and biologically important messenger molecule that regulates vascular homeostasis at sites of vessel wall injury. We have recently discovered that SMC generate CO from the catabolism of heme oxygenase-1 (HO-1) and that specific humoral and hemodynamic factors encountered in the microenvironment of vascular injury induces HO-1 gene expression and CO release. Based on these findings, we propose to study the biological effects of CO on vascular SMC function. These studies will determine the effect of both exogenously administered and endogenously-derived CO on blood vessel tone, SMC proliferation, and SMC collagen synthesis. In all instances where CO is shown to alter SMC function we will determine the molecular basis of this effect. Since we have shown that Co stimulates soluble guanylate cyclase activity in vascular SMC, we will investigate whether cGMP and protein kinase G (PKG) and/or A (PKA) mediates the biological effects of CO. We will further explore the role of CO as an autocrine regulator of SMC function by generating SMC that over-express HO-1 enzyme. If HO-1 transfected SMC have altered biological responses we will attempt to restore responses by treating SMC with specific metalloprotoporphyrin HO inhibitors or by treating SMC with HO-1 antisense oligodeoxynucleotides. Finally, we will investigate the role of CO in regulating intimal thickening and vascular reactivity in the rat carotid artery balloon injury model. We will determine whether the local inhibition or over-expression of HO-1 activity and CO production regulates lesion formation and vascular tone at sites of vascular injury. In addition, we will determine whether cGMP and PKG/PKA are responsible for any of the in vivo effects of CO. It is anticipated that these studies will (a) establish CO as a novel SMC-derived signaling molecule that regulates SMC contraction, proliferation and collagen synthesis, and (b) lead to the development of novel therapeutic strategies in treating occlusive vascular disease.