权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Molecular coupling required for intracellular calcium release that regulates synaptic depression

调节突触抑制的细胞内钙释放所需的分子偶联

基本信息

批准号：
13480266
负责人：
KATO Nobuo
金额：
$ 8.38万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2003
项目状态：
已结题

项目摘要

Induction of synaptic plasticity, such as long-term potentiation (LTP) and long-term depression (LTD), is believed to require synaptically induced Ca2+ rises. Although LTP is thought to be induced by large rises of Ca2+, two different mechanisms have been proposed for LTD induction : one is LTD induction by intracellular Ca2+ release, whereas the other mechanism depends on moderate rises of Ca2+ from whatever calcium sources. We studied whether both of these LTD induction mechanisms operate and, if so, how these mechanisms cooperate. Under pharmacological manipulations, LTD induction was attempted by using conditioning stimulations of different frequencies, and relationship were seeked for between the magnitude of LTD and the extent of intracellular Ca2+ rises. With 0.5-1.0 Hz stimulation, LTD induction depends crucially on the calcium source but not on the amount of calcium rise, and calcium release facilitated LTD induction with calcium influx via L-type calcium channel inhibiting it … More . At 0.5 Hz, a ryanodine receptor agonist, caffeine, and an L-type Ca2+ channel blocker, nifedipine, both enhanced the magnitude of LTD. At 1Hz, an internal Ca2+ stone depletor, thapsigargin and an L-type Ca2+ channel activator, S (-)-BAY K8644, both decreased LTD magnitude. At 2Hz, however, the change in synaptic efficiency was in parallel with the amount of Ca2+ rises. From these findings, we conclude that the two mechanisms are both involved in LTD induction but separately at two different levels of postsynaptic activation : the source dependent mechanism operate at lower postspaptic activation ranges than the calcium concentration dependent mechanism does. Relationship between LTD induction mechanisms detailed above and the novel calcium release mechanisms that we have observed (IP3-assisted CICR) has also been investigated. The results suggested a hitherto unknown role of the adaptor protein Homerla in enabling activity-dependent enhancement of calcium signal, which is likely to interfere with rules of synaptic modification. Less

突触可塑性的诱导，如长时程增强（LTP）和长时程抑制（LTD），被认为需要突触诱导的Ca 2+升高。虽然LTP被认为是由Ca 2+的大幅上升引起的，但已经提出了两种不同的机制用于LTD诱导：一种是通过细胞内Ca 2+释放的LTD诱导，而另一种机制取决于来自任何钙源的Ca 2+的适度上升。我们研究了这两种LTD诱导机制是否起作用，如果是的话，这些机制是如何合作的。在药理学操作下，尝试用不同频率的条件刺激诱导LTD，并寻找LTD的大小与细胞内Ca ~（2+）升高程度之间的关系。在0.5- 1.0Hz刺激下，LTD的诱导主要依赖于钙源，而不依赖于钙升高的量，钙释放促进LTD的诱导，而钙内流通过L-型钙通道抑制LTD的诱导 ...更多信息 .在0.5 Hz时，ryanodine受体激动剂咖啡因和L型钙通道阻滞剂硝苯地平均增强LTD的幅度。在1 Hz时，内部钙结石清除剂毒胡萝卜素和L型钙通道激活剂S（-）-BAY K8644均降低LTD的幅度。而在2 Hz时，突触效率的变化与Ca ~（2+）升高的量平行。从这些发现中，我们得出结论，这两种机制都参与LTD诱导，但分别在两个不同的水平的突触后激活：源依赖性机制在较低的postspaptic激活范围比钙浓度依赖性机制。还研究了上文详述的LTD诱导机制与我们观察到的新型钙释放机制（IP 3辅助的CICR）之间的关系。结果表明，衔接蛋白Homerla在使钙信号的活性依赖性增强中的作用是迄今为止未知的，这可能会干扰突触修饰的规则。少

项目成果

期刊论文数量（40）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Yamamoto et al.: "Emergence of a functional coupling between inositol-1,4,5-tris phosphate receptors and calcium channels in developing neocortical neurons"Neuroscience. (in press).

Yamamoto 等人：“在发育中的新皮质神经元中肌醇-1,4,5-三磷酸受体和钙通道之间功能耦合的出现”神经科学。

DOI：
发表时间：
期刊：
影响因子：
0
作者：
通讯作者：

Yoshimura et al.: "Age-dependent appearance of an insulo-parietal cortical signal propagation that elicits a synchronized population oscillation in the parietal cortex in rats."Dev Brain Res. 143. 245-251 (2003)

Yoshimura 等人：“岛-顶叶皮层信号传播的年龄依赖性外观，引起大鼠顶叶皮层的同步群体振荡。”Dev Brain Res。

DOI：
发表时间：
期刊：
影响因子：
0
作者：
通讯作者：

Yoshimura et al.: "Age-dependent emergence of oscillatory signal flow between the primary and secondary visual cortices in rat brain slices"Brain Res. 990. 172-181 (2003)

Yoshimura 等人：“大鼠脑切片中初级和次级视觉皮层之间振荡信号流的年龄依赖性出现”Brain Res。

DOI：
发表时间：
期刊：
影响因子：
0
作者：
通讯作者：

Yamamoto et al.: "A distinct form of calcium release downregulates membrane excitability in neocortical-L pyramidal cells"Neuroscience. 109. 665-676 (2002)

Yamamoto 等人：“钙释放的一种独特形式会下调新皮质-L 锥体细胞的膜兴奋性”神经科学。

DOI：
发表时间：
期刊：
影响因子：
0
作者：
通讯作者：

To-and-fro optical voltage signal propagation between the insular gustatory an dparietal oral somatosensory areas in rat cortex slices

大鼠皮层切片中岛叶味觉和顶叶口腔体感区域之间的来回光电压信号传播

DOI：
发表时间：
2004
期刊：
Brain Res 1015
影响因子：
0
作者：
Takeshi Soda;Ryo Nakashima;Dai Watanabe;Kazunori Nakajima;Ira Pastan;Shigetada Nakanishi;Yoshimura et al.
通讯作者：
Yoshimura et al.