Mechanisms of stimuli discrimination and transduction in gustatory and olfactory cells

味觉和嗅觉细胞的刺激辨别和转导机制

基本信息

批准号：
60480457
负责人：
KURIHARA Kenzo
金额：
$ 1.22万
依托单位：
Hokkaido University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1985
资助国家：
日本
起止时间：
1985 至 1986
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-60480457/
关键词：
Taste cell Olfactory cell Neuroblastoma Liposome Membrane Potential Phase boundary potential ニオイ

项目摘要

The discrimination mechanisms of chemical stimuli in taste and olfactory cells were studied using taste cells, neuroblastoma and liposomes. Among various taste stimuli, bitter substances were found to adsorb on lipid layers of the membranes, which leads to generation of the receptor potentials. "Taste blind" for phenylthiocarbamide in man was examined in terms of difference in lipid composition of the receptor membranes. As for the discrimination of odorants, various mechanisms have been proposed. Many investigators have believed that there exist specific receptor protein for each odorant, but question arises whether or not animals have respective specific receptor proteins for numerous odorants. We found that neuroblastoma cells and liposomes having certain lipid compositions are depolarized by various odorants similarly to olfactory cells. Changes in the lipid composition led to changes in specificity to various odorants. The present results suggested that odorant discrimination can be explained by posturating that lipid composition of receptor membrane of each olfactory cell is different from one cell to another.The mechanisms of changes in the membrane potentials in response to various taste stimuli and odorants were examined using taste organs, neuroblastoma, isolated olfactory cells and liposomes. Exchanges of ions in external medium with impermeable ions did not affect the changes of the membrane potentials in response to chemical stimuli. The membrane potential changes of lipid bilayer membranes in response to bitter substances and odorants occurred under the conditions that ion concentration at both sides of membranes is the same, suggesting that the membrane potential changes are induced by changes in the phase boundary potentials.

使用味觉细胞，神经母细胞瘤和脂质体研究了味觉和嗅觉细胞中化学刺激的区分机制。在各种味道刺激中，发现苦味物质会吸附在膜的脂质层上，从而导致受体电位的产生。根据受体膜的脂质组成的差异，检查了人类苯三甲酰胺的“味觉盲”。至于歧视气味，已经提出了各种机制。许多研究者认为，每种气味都存在特定的受体蛋白，但是问题出现了动物是否具有多种气味剂的特定受体蛋白。我们发现，具有某些脂质组合物的神经母细胞瘤细胞和脂质体被各种气味剂与嗅觉细胞相似。脂质组成的变化导致对各种气味的特异性变化。目前的结果表明，可以通过姿势表明每个嗅觉细胞的受体膜的脂质组成可以解释气味歧视，从一个细胞到另一个细胞都不同。使用味道和神经细胞瘤，分离的嗅觉嗅觉，膜刺激和气味检查，膜电位变化的机制。具有不可渗透离子的外部培养基中离子的交换不会影响响应化学刺激的膜电位的变化。脂质双层膜的膜电位变化是在苦味物质和气味的响应下发生的，这是在膜两侧的离子浓度相同的条件下，这表明膜电位变化是由相边界电位变化引起的。