Store calcium mediates cholinergic effects on mIPSCs in the rat main olfactory bulb
Store calcium mediates cholinergic effects on mIPSCs in the rat main olfactory bulb
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DOI：
10.1152/jn.00757.2005
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发表时间：
2006-03-01
影响因子：
2.5
通讯作者：
Vijayaraghavan, S
中科院分区：
文献类型：
--
作者：
Ghatpande, AS;Sivaraaman, K;Vijayaraghavan, S
内质网（ER）钙库在调节递质释放中的重要性正逐渐被人们所认识。乙酰胆碱（ACh）是一种可能在调节中枢神经系统中递质释放的钙储备中起重要作用的递质系统。主嗅球（OB）接受丰富的胆碱能神经支配的水平分支的对角带的布罗卡和阻断胆碱能信号在灯泡抑制动物的能力，以区分密切相关的气味。在这里，我们表明，暴露OB片氨甲酰胆碱（CCh），抗水解的乙酰胆碱类似物，增加γ-氨基丁酸（GABA）的释放在树突状突触到二尖瓣细胞。这种递质释放的增加是由M1类毒蕈碱受体的激活介导的，并且需要从ER动员钙。CCh的作用部位受发育调控。在小于出生后第10天的动物中，CCh的主要作用似乎是在二尖瓣细胞上，通过二尖瓣细胞谷氨酸释放增加引起的相互信号传导来增强GABA释放。在出生后10天以上的动物中，CCh似乎调节中间神经元树突本身的递质释放。我们的研究结果指出，抑制的调制作为一个重要的作用，胆碱能信号在OB。我们的数据也加强了一个新的想法，即在调节中枢神经系统突触递质释放的钙储存的作用。
The significance of endoplasmic reticulum ( ER) store calcium in modulating transmitter release is slowly gaining recognition. One transmitter system that might play an important role in store calcium modulation of transmitter release in the CNS is acetylcholine (ACh). The main olfactory bulb ( OB) receives rich cholinergic innervation from the horizontal limb of the diagonal band of Broca and blocking cholinergic signaling in the bulb inhibits the ability of animals to discriminate between closely related odors. Here we show that exposing OB slices to carbamylcholine (CCh), a hydrolysis-resistant analog of Ach, increases gamma-aminobutyric acid (GABA) release at dendrodendritic synapses onto the mitral cells. This increase in transmitter release is mediated by the activation of the M1 class of muscarinic receptors and requires the mobilization of calcium from the ER. The site of action of CCh for this effect is developmentally regulated. In animals younger than postnatal day 10, the major action of CCh appears to be on mitral cells, enhancing GABA release by reciprocal signaling resulting from increased glutamate release from mitral cells. In animals older than postnatal day 10, CCh appears to modulate transmitter release from dendrites of the interneurons themselves. Our results point to modulation of inhibition as an important role for cholinergic signaling in the OB. Our data also strengthen the emerging idea of a role for store calcium in modulating transmitter release at CNS synapses.