cGMP-dependent protein kinase I as a new target against stroke

可溶性鸟苷酸介导NO保护脑卒中损伤的信号通路 环化酶活化和环鸟苷一磷酸（ cGMP） 阵然而， 从cGMP到平滑肌细胞（SMC）的下游信号传导仍然不完全清楚。cGMP- 依赖性蛋白激酶I（cGKI）是cGMP信号传导的关键介质。我们的初步结果表明， cGKI SMC的大脑中动脉再灌注减弱，卒中损伤更明显 特异性可诱导的条件性基因敲除小鼠比野生型小鼠更明显，表明cGKI在 SMC对脑再灌注损伤的保护作用。 这个项目的总体目标是确定保护作用的分子机制 cGKI信号转导在SMC对抗中风损伤中的作用。我们将检验cGKI介导保护性细胞凋亡的假设。 cGMP的保护作用和cGMP-cGKI信号传导的保护作用是SMC特异性的。 我们将利用小鼠的诱导 cGKI基因敲除 SMC 专门研究 SMC依赖性血管机制对cGMP抗中风保护作用的贡献。 我们 目的是（1）确定cGKI SMC依赖性机制对卒中保护作用的作用， (2)以确定其分子机制 cGKI-SMC信号通路的保护作用 中风损伤。 这些结果将使开发新的中风特异性治疗方法成为可能。 假设平滑肌细胞中的GKI可以预防中风。 目的1：确定cGKI介导的SMC信号转导与细胞凋亡的相关性及其机制。 中风保护。我们将研究SMC中cGKI缺乏是否会影响cGKI SMC中的卒中结局。 特异性基因敲除小鼠我们将比较cGKI敲除小鼠和cGKI野生型小鼠的卒中结局。我们 将确定大脑中动脉闭塞和再灌注后的神经功能缺损和梗死体积 动脉，并比较基线和缺血和再灌注期间的脑血流量。 目的2：研究平滑肌细胞cGKI在血管反应性中的作用。我们将测试cGKI缺失是否 在SMC中损害离体血管的反应性、脑血流量和自动调节。 目的3：探讨血小板和白细胞在cGKI缺陷型SMC脑卒中损伤中的作用 小鼠脑微血管内的血小板聚集和白细胞积聚是脑血管病的关键因素。 中风损伤我们将研究SMC中cGKI缺乏如何影响血小板聚集和白细胞的作用。 中风损伤的积累。 我们预期，本提案中描述的研究将建立一种新的中风小鼠模型 研究和进一步了解cGKI SMC信号传导在预防中风中的作用。这些 结果将是至关重要的，为开发cGKI升高化合物提供科学基础， 中风患者的治疗药物。

The signaling pathways by which NO protects against stroke injury are mediated by soluble guanylyl cyclase activation and cyclic guanosine monophosphate ( cGMP) formation. However, the mechanisms of downstream signaling from cGMP to smooth muscle cells (SMC) remain incompletely understood. The cGMP- dependent protein kinase I (cGKI) is a key mediator of cGMP signaling. Our preliminary results indicate that reperfusion of middle cerebral artery was attenuated and stroke injury was more pronounced in cGKI SMC specific inducible conditional knockout mice than in wild-type mice, suggesting a protective role for cGKI in SMC against cerebral reperfusion injury. The overall goal of this project is to identify the molecular mechanisms underlying the protective effect of cGKI signaling in SMC against stroke injury. We will test the hypotheses that cGKI mediate the protective effects of cGMP and that the protective effects of cGMP-cGKI signaling are SMC specific. We will take advantage of mice with inducible knockout of cGKI in SMC to specifically study the contributions of SMC-dependent vascular mechanisms to the protective effects of cGMP against stroke. Our goals are (1) to determine the role of cGKI SMC-dependent mechanisms to the protective effect in stroke and (2) to identify the molecular mechanisms underlying the protective role of cGKI-SMC signaling in stroke injury. These results will make possible the development of new specific therapeutic approaches to stroke. HypothesiscGKI in smooth muscle cells protects against stroke. Aim 1: To determine the relevance and mechanism of cGKI-mediated signaling in SMC for stroke protection. We will study whether deficiency of cGKI in SMC worsens stroke outcome in cGKI SMC- specific knockout mice. We will compare stroke outcome in cGKI knockout mice and cGKI wild-type mice. We will determine neurological deficit and infarct volume after occlusion and reperfusion of the middle cerebral artery and compare cerebral blood flow at baseline and during ischemia and reperfusion. Aim 2: To study the role of cGKI of SMC in vascular reactivity. We will test whether cGKI deletion in SMC impairs reactivity of isolated vessels, cerebral blood flow and autoregulation. Aim 3: To investigate the role of platelets and leukocytes in stroke injury of cGKI SMC deficient mice. Platelets aggregation and accumulation of leukocytes within cerebral microvessels is critically involved in stroke injury. We will study how cGKI deficiency in SMC affects the role of platelet aggregation and leukocytes accumulation in stroke injury. We anticipate that studies described in this proposal will establish a new mouse model for stroke studies and further our knowledge on the role of cGKI SMC signaling in the protection against stroke. These results will be critical to provide the scientific foundation for the development of cGKI-elevating compounds as therapeutic agents in stroke patients.