IONIC CHANNELS IN DISSOCIATED SMOOTH MUSCLE CELLS

解离平滑肌细胞中的离子通道

• 批准号: 6124897
• 负责人: JOHN V WALSH
• 金额: $ 41.2万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 1983
• 资助国家: 美国
• 起止时间: 1983-01-01 至 2001-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6124897
• 关键词: 3T3 cells; NMDA receptors; Xenopus; Xenopus oocyte; acyl coA; albumins; bradykinin; complementary DNA; fatty acid binding protein; fatty acids; gene deletion mutation; laboratory rabbit; messenger RNA; molecular cloning; muscle pharmacology; nuclear magnetic resonance spectroscopy; phospholipase A2; phospholipase inhibitor; potassium channel; site directed mutagenesis; sphingosine; stretch reflex; toad; vascular smooth muscle; voltage /patch clamp

This proposal is an outgrowth of studies of the effects of arachidonic acid and other long chain fatty acids on ion channels in smooth muscle cells. These studies along with preliminary data gathered for the present proposal make it quite unlikely that these fatty acids act in a non- specific way on the lipid bilayer and suggest strongly that they act on the ion channels themselves or on a closely related protein. The present proposal is directed at two basic questions and employs the NMDA receptor and large conductance Ca++activated K+ channels to answer them. First, do the effects of long chain fatty acids like arachidonate involve a fatty acid binding site on the channel protein? And specifically, in the case of the NMDA receptor, is that binding site a region on the NMDAR1 subunit which we have discovered is homologous to the superfamily of cytosolic fatty acid binding proteins? Chimeric channels and channels with single- residue mutations will be studied electrophysiologically in several expression systems to answer this question. In addition 2D NMR will be used to study the structure of the putative NMDAR1 fatty acid binding region which will be overexpressed. Second, what is the physiological role of long-chain fatty acid action on ion channels? Do the fatty acids mediate the action of neurotransmitters on ion channels or the effects of stretch, the latter through mechanosensitive phospholipases? ADIFAB, a fluorescent ratiometric indicator of long-chain fatty acids, will be used to measure fatty acid production in response to stretch and neurotransmitter action. Agents that act as sinks for fatty acids or block their production will also be employed in a subset of the studies using ADIFAB. In both stroke and myocardial ischemia abnormally high levels of fatty acids are gene rated, and they may either contribute to cellular injury, as in their action on NMDA receptors in stroke, or perhaps exert a protective effect as by their action on K+ channels in heart. New therapies based on an understanding of long chain fatty acid action on ion channels are possible for both conditions but seem especially likely in the case of stroke where NMDA receptor activation appears to be a major factor in the pathophysiology.

该提案是花生四烯酸影响研究的产物 平滑肌离子通道上的酸和其他长链脂肪酸 细胞。这些研究以及目前收集的初步数据 该提案使得这些脂肪酸不太可能以非- 脂双层上的特定方式并强烈表明它们作用于 离子通道本身或密切相关的蛋白质。现在的 该提案针对两个基本问题并采用 NMDA 受体 大电导Ca++激活K+通道来回答它们。首先，做 长链脂肪酸如花生四烯酸的作用涉及脂肪 通道蛋白上的酸结合位点？具体来说，在以下情况下 NMDA 受体，是 NMDAR1 亚基上的一个区域的结合位点 我们发现它与胞质超家族同源 脂肪酸结合蛋白？嵌合通道和单通道 残基突变将在几个方面进行电生理学研究 表达系统来回答这个问题。此外，2D NMR 将 用于研究假定的 NMDAR1 脂肪酸结合的结构 将被过度表达的区域。二、生理作用是什么 长链脂肪酸对离子通道的作用？做脂肪酸吗 介导神经递质对离子通道的作用或 拉伸，后者通过机械敏感磷脂酶？阿迪法布 将使用长链脂肪酸的荧光比率指示剂 测量脂肪酸的产生以响应拉伸和 神经递质的作用。充当脂肪酸接收器或阻滞剂 他们的生产也将用于使用的研究的子集 阿迪法布。 在中风和心肌缺血中，脂肪含量异常高 酸是基因决定的，它们可能会导致细胞损伤， 例如它们对中风中 NMDA 受体的作用，或者可能发挥作用 通过对心脏 K+ 通道的作用发挥保护作用。新的 基于长链脂肪酸对离子作用的理解的疗法 渠道对于这两种情况都是可能的，但似乎特别有可能在 NMDA 受体激活似乎是中风的主要原因 病理生理学因素。

项目成果

Stretch activation of a toad smooth muscle K+ channel may be mediated by fatty acids.

蟾蜍平滑肌 K 通道的伸展激活可能是由脂肪酸介导的。

• DOI: 10.1113/jphysiol.1995.sp020668
• 发表时间: 1995
• 期刊: The Journal of physiology
• 作者: Ordway,RW;Petrou,S;Kirber,MT;WalshJr,JV;Singer,JJ
• 通讯作者: Singer,JJ

Substance P, like acetylcholine, augments one type of Ca2+ current in isolated smooth muscle cells.

P 物质与乙酰胆碱一样，可增强分离的平滑肌细胞中的一种 Ca2 电流。

• DOI: 10.1007/bf00594191
• 发表时间: 1989
• 期刊: Pflugers Archiv : European journal of physiology
• 作者: Clapp,LH;Vivaudou,MB;Singer,JJ;WalshJr,JV
• 通讯作者: WalshJr,JV

Role for diacylglycerol in mediating the actions of ACh on M-current in gastric smooth muscle cells.

二酰基甘油在介导 ACh 对胃平滑肌细胞 M 电流作用中的作用。

• DOI: 10.1152/ajpcell.1992.263.6.c1274
• 发表时间: 1992
• 期刊: The American journal of physiology
• 作者: Clapp,LH;Sims,SM;Singer,JJ;WalshJr,JV
• 通讯作者: WalshJr,JV

Regulation of one type of Ca2+ current in smooth muscle cells by diacylglycerol and acetylcholine.

二酰甘油和乙酰胆碱对平滑肌细胞中一种 Ca2 电流的调节。

• DOI: 10.1096/fasebj.2.9.2453389
• 发表时间: 1988
• 期刊: FASEB journal : official publication of the Federation of American Societies for Experimental Biology
• 作者: Vivaudou,MB;Clapp,LH;WalshJr,JV;Singer,JJ
• 通讯作者: Singer,JJ

Multiple types of Ca2+ channels in visceral smooth muscle cells.

内脏平滑肌细胞中多种类型的 Ca2 通道。

• DOI: 10.1007/bf00370463
• 发表时间: 1991
• 期刊: Pflugers Archiv : European journal of physiology
• 作者: Vivaudou,MB;Singer,JJ;WalshJr,JV
• 通讯作者: WalshJr,JV