CONTRACTION OF VASCULAR SMOOTH MUSCLE CELLS

血管平滑肌细胞的收缩

• 批准号: 2685347
• 负责人: KATHLEEN G MORGAN
• 金额: $ 19.49万
• 依托单位: BOSTON BIOMEDICAL RESEARCH INSTITUTE
• 依托单位国家: 美国
• 财政年份: 1989
• 资助国家: 美国
• 起止时间: 1989-04-01 至 2001-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2685347
• 关键词: biological signal transduction; calcium flux; caldesmon; calponin; enzyme induction /repression; ferrets; isozymes; mitogen activated protein kinase; muscle contraction; muscle tone; neural transmission; protein kinase C; protein structure function; second messengers; tissue /cell culture; vascular smooth muscle

This proposal represents the next five years of a long-standing research program, the general focus of which continues to be a determination of the mechanism of protein kinase C (PKC)-dependent contraction of vascular smooth muscle cells. The general aim of the next five years will be to test the specific hypothesis that PKC-mediated contraction of vascular smooth muscle cells involves thin filament regulation. The specific aims are: (1) to test the hypothesis that calponin (CaP) is a physiologically important regulator of vascular tone by determining the effects of fragments and peptides of CaP in permeabilized single freshly dissociated cells; (2) to test the hypothesis that PKC and CaP are linked in a signaling cascade involving cytoskeIetal elements that results in the observed PKC-dependent redistribution of CaP by: (a) determining the structures from which and to which CaP associates upon PKC activations and, (b) determining what other signaling molecules are involved in the cascade; (3) to test the hypothesis that caldesmon (CaD) is a physiologically important regulator of vascular tone b: (a) monitoring its phosphorylation levels, (b) extending past studies on a C terminal CaD peptide, and (c) determining the effect of the fragments of the N- terminus of CaD on tone development, maintenance, relaxation and cytoskeletal architecture; (4) to test the hypothesis that signaling steps between PKC activation and mitogen-activated protein kinase (MAPK) redistribution/activation involve recruitment of Raf kinase and MAPK kinase (MEK) and to test whether phosphorylation/activation of MAPK plays a role in its biphasic subcellular targeting; (5) to determine the degree to which the observed MAP kinase-related contraction is selectively caused by upstream activation of PKC-epsilon as opposed to other isoforms. Experiments will be performed using two prototypical vascular smooth muscles from the ferret, the phasic portal vein, and the tonic aorta. The proposal is based on progress made in this laboratory, as well as other laboratories over the last grant period demonstrating a role for PKC-mediated contraction of differentiated vascular smooth muscle cells. The studies outlined are aimed at elucidating the details of the mechanisms involved in this contraction. The results obtained will either help to prove, or disprove, the hypothesis of PKC-mediated thin filament regulation. In either case, the information will be of broad general interest.

该提案代表了未来五年的长期研究 计划，其总体重点仍然是确定 蛋白激酶C（PKC）依赖性血管收缩机制 平滑肌细胞。未来五年的总体目标是 检验 PKC 介导的血管收缩的具体假设 平滑肌细胞涉及细丝调节。具体目标 是：（1）检验钙调蛋白（CaP）是一种生理学的假设 通过确定血管张力的重要调节剂 透化单个新鲜解离的 CaP 片段和肽 细胞； (2) 检验 PKC 和 CaP 相关的假设 涉及细胞骨架元件的信号级联反应导致 通过以下方式观察到 PKC 依赖性的 CaP 重新分布：(a) 确定 PKC 激活后 CaP 结合的结构 (b) 确定哪些其他信号分子参与了 级联; (3) 检验 caldesmon (CaD) 是 生理上重要的血管张力调节器 b：(a) 监测 其磷酸化水平，(b) 扩展过去对 C 末端的研究 CaD 肽，以及 (c) 确定 N-片段的作用 CaD 的终点是音调发展、维持、放松和 细胞骨架结构； (4) 检验假设信号 PKC 激活和丝裂原激活蛋白激酶 (MAPK) 之间的步骤 重新分布/激活涉及 Raf 激酶和 MAPK 的募集 激酶 (MEK) 并测试 MAPK 的磷酸化/激活是否发挥作用 在其双相亚细胞靶向中发挥作用； (5)确定程度 观察到的 MAP 激酶相关收缩是选择性的 由 PKC-epsilon 的上游激活引起，而不是其他 同工型。实验将使用两种典型的血管进行 来自雪貂的平滑肌、阶段性门静脉和补品 主动脉。该提案也是基于该实验室取得的进展 正如其他实验室在上一个资助期内所展示的作用一样 PKC 介导的分化血管平滑肌细胞的收缩。 概述的研究旨在阐明 参与这种收缩的机制。获得的结果将是 有助于证明或反驳 PKC 介导的细丝假说 规定。无论哪种情况，信息都将具有广泛的一般性 兴趣。