Molecular-biological and pharmacological analysis of regulating sites of glycine receptor function in Xenopus oocytes using novel compounds

使用新型化合物对非洲爪蟾卵母细胞甘氨酸受体功能调节位点进行分子生物学和药理学分析

• 批准号: 11672266
• 负责人: TAKAHAMA Kazuo
• 金额: $ 2.18万
• 依托单位: Kumamoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11672266/
• 关键词: Glycine receptor; Dextromethorphan; Strychnine; Xenopus oocytes; α_1subunit; α_2subunit; Point mutant; Inwardly rectifing K^+ channel; Morphan compounds; α2サブユニット; 遅延整流性Kイオンチャネル

We have previously reported that dextromethorphan (DM), one of morphan derivatives, inhibited glycine-induced currents in single neuron acutely dissociated from rat brain. This study was designed to clarify the regulating site of glycine receptor function and to get further information about the action of DM and antitussives on other neuronal receptors and channels.【Results】1) DM, strychnine, codeine and caffeine inhibited the glycine-induced cur-rents in Xenopus oocytes expressing α_1-or α_2a-subunit of glycine receptor. IC_<50S> for DM and codeine were 5.2x10^<-5>M and 2.2x10^<-4>M, respectively, in the α_1, and 1.2x10^<-5>M and 5.5x10^<-5> M, respectively in the α_2. Both drugs showed more potent inhibitory action on the α_2 than α_1, while the reverse was true for strychnine and caffeine. 2) Out of newly synthesized 11 compounds, which have a morphan structure in the molecule, three compounds inhibited the currents induced by glycine in Xenopus oocytes expressing the α_1 subunit. 3) In the mutants, Y161F, F159Y/Y161F and S267I, of the α_1, the inhibitory action of DM was not changed, compared with the action in the wild type. On the other hand, the action of strychnine was potentiated in the double mutant, F159Y/Y161F than in the wild type. 4) In patch-clamp study using acutely dissociated dorsal raphe neurons of rats, DM inhibited not only the K^+ currents induced by 5-HT with 1.43x10^<-5> M of the IC_<50>, but also the currents irreversibly activated by intracellular GTPγS even in the absence of 5-HT.The results sugest that (1) the morphan structure might be a part of chemical structure essential for modifing the function of glycine receptors, (2) DM may have a site on the glycine receptor different from the site where Str acts.

我们以前报道了Xtromethorphan（DM），一种形态的衍生物之一，抑制了甘氨酸诱导的单神经元中的电流，从大鼠脑中敏感其他神经元和通道上的抗呼吸器。 > m和2.2x10^<-4> m，在α_1中进行尊敬，1.2x10^<-5> m和1.2x10^<-5>α__分子中具有形态结构的组合，三个抑制了甘氨酸在Xenopus卵母细胞中诱导的货币，而α_1亚基与野生型的作用相比没有改变。双重突变体F159Y/Y161F比野生型中的大鼠Al Raphi神经元不仅抑制了IC_ <50> 1.43x10^<-5> m的5-HT诱导的K^+电流（1）形态结构可能是修饰甘氨酸受体功能所必需的化学结构的一部分，（2）DM在甘氨酸受体上可能具有与STR作用的位点不同的甘氨酸受体。

项目成果

Yoshinaka Murai,Kazuo Takahama,Norio Akaike.: "Preferential inhibition of L-and N-type calcium channels in the rat hippocampal neurons by cilnidipine."Brain Research. 854. 6-10 (2000)

Yoshinaka Murai、Kazuo Takahama、Norio Akaike.：“西尼地平优先抑制大鼠海马神经元中的 L 型和 N 型钙通道。”大脑研究。

Hitoshi Ishibashi,Takanobu Mochidome,Kazuo Takahama.: "Activation of potassium conductance by ophiopogonin-D in acutely dissociated rat paratracheal neurones."British.J.Pharmacol.. 132. 461-466 (2001)

Hitoshi Ishibashi、Takanobu Mochidome、Kazuo Takahama.：“麦冬皂苷-D 在急性分离的大鼠气管旁神经元中激活钾电导。”British.J.Pharmacol.. 132. 461-466 (2001)

Hitoshi Ishibashi,Kouichi Kuwano,Kazuo Takahama.: "Inhibition of the 5-HT1A receptor-mediated inwardly rectifying K^+ current by dextromethorphan in rat dorsal raphe neurons"Neuropharmacology. 39. 2302-2308 (2000)

Hitoshi Ishibashi，Kouichi Kuwano，Kazuo Takahama.：“右美沙芬对大鼠中缝背侧神经元中 5-HT1A 受体介导的内向整流 K 电流的抑制”神经药理学。

Hitoshi Ishibashi, Takanobu Mochidome, Junpei Okai, Hiroyuki Ichiki, Hideaki Shimada, Kazuo Takahama.: "Activation of potassium conductance by ophio-pogonin-D in acutely dissociated rat paratracheal neurones."British.J.Pharmacol.. 132. 461-466 (2001)

Hitoshi Ishibashi、Takanobu Mochidome、Junpei Okai、Hiroyuki Ichiki、Hideaki Shimada、Kazuo Takahama.：“ophio-pogonin-D 在急性分离的大鼠气管旁神经元中激活钾电导。”British.J.Pharmacol.. 132. 461-466

Yoshinaka Murai, Hisayuki Uneyama, Hitoshi Ishibashi, Kazuo Takahama, Norio Akaike.: "Preferential inhibition of L-and N-type calcium channels in the rat hippocampal neurons by cilnidipine."Brain Research. 854. 6-10 (2000)

Yoshinaka Murai、Hisayuki Uneyama、Hitoshi Ishibashi、Kazuo Takahama、Norio Akaike：“西尼地平优先抑制大鼠海马神经元中的 L 型和 N 型钙通道。”大脑研究。