Single channel analysis of the blocking actions of BIDN and fipronil on a Drosophila melanogaster GABA receptor (RDL) stably expressed in a Drosophila cell line
Single channel analysis of the blocking actions of BIDN and fipronil on a Drosophila melanogaster GABA receptor (RDL) stably expressed in a Drosophila cell line
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BIDN 和氟虫腈对果蝇细胞系中稳定表达的果蝇 GABA 受体 (RDL) 的阻断作用的单通道分析
DOI：
10.1038/sj.bjp.0703507
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发表时间：
2000
影响因子：
7.3
通讯作者：
D. Sattelle
中科院分区：
文献类型：
--
作者：
F. Grolleau;D. Sattelle
从稳定表达野生型RDLac黑腹果蝇同聚体形成离子型GABA受体亚基（狄氏剂抗性基因Rdl的产物）的果蝇S2细胞系中获得单通道记录。在−60 mV的保持电位下，通过压力喷射将 GABA（50μM）应用于S2-RDL细胞的外向贴片。 100 μM印防己毒素（PTX）可完全阻断内向电流。 单位电流-电压关系在负电位下呈线性，但在大于0 mV的电位下显示轻微向内整流。 电流的反转电位（EGABA=-1.4 mV）接近计算的氯平衡电位。 GABA引起的单通道电导为36 pS。 当用于喷射GABA的脉冲持续时间长于80 ms时，还观察到71 pS电导通道。 单一事件的平均开放时间分布最好地拟合两个指数函数，表明两个开放通道状态。当1 μM非泼罗尼或1 μM BIDN存在于外部盐水中时，GABA门控通道完全阻断。 当以接近抑制开放概率的IC 50值（281 nM，BIDN; 240 nM，非泼罗尼）的浓度应用BIDN或非泼罗尼时，通道开放的持续时间缩短。 此外，BIDN的阻断作用导致了一种新的通道电导（17 pS）的出现。 检查了BIDN和氟虫腈联合应用的效果。BIDN（300 nM）与不同浓度（100-1000 nM）的非泼罗尼共同给药导致BIDN诱导的最大Po值进一步剂量依赖性降低。 因此，BIDN和氟虫腈都缩短了野生型RDLac GABA受体通道开放的持续时间，但似乎作用于不同的位点。
Single channel recordings were obtained from a Drosophila S2 cell line stably expressing the wild‐type RDLac Drosophila melanogaster homomer‐forming ionotropic GABA receptor subunit, a product of the resistance to dieldrin gene, Rdl. GABA (50 μM) was applied by pressure ejection to outside‐out patches from S2‐RDL cells at a holding potential of −60 mV. The resulting inward current was completely blocked by 100 μM picrotoxin (PTX). The unitary current‐voltage relationship was linear at negative potentials but showed slight inward rectification at potentials more positive than 0 mV. The reversal potential of the current (EGABA=−1.4 mV) was close to the calculated chloride equilibrium potential. The single channel conductance elicited by GABA was 36 pS. A 71 pS conductance channel was also observed when the duration of the pulse, used to eject GABA, was longer than 80 ms. The mean open time distribution of the unitary events was fitted best by two exponential functions suggesting two open channel states. When either 1 μM fipronil or 1 μM BIDN was present in the external saline, the GABA‐gated channels were completely blocked. When BIDN or fipronil was applied at a concentration close to the IC50 value for suppression of open probability (281 nM, BIDN; 240 nM, fipronil), the duration of channel openings was shortened. In addition, the blocking action of BIDN resulted in the appearance of a novel channel conductance (17 pS). The effects of co‐application of BIDN and fipronil were examined. Co‐application of BIDN (300 nM) with various concentrations (100–1000 nM) of fipronil resulted in an additional BIDN‐induced dose‐dependent reduction of the maximum Po value. Thus both BIDN and fipronil shorten the duration of wild‐type RDLac GABA receptor channel openings but appear to act at distinct sites.
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DOI：
10.1113/jphysiol.1994.sp020278
发表时间：
1994-08
期刊：
The Journal of Physiology
影响因子：
--
作者：
H. G. Zhang;R. ffrench-Constant;M. Jackson
通讯作者：
H. G. Zhang;R. ffrench-Constant;M. Jackson
影响因子：
3.6
作者：
H. G. Zhang;H. Lee;T. Rocheleau;R. ffrench-Constant;M. Jackson
通讯作者：
H. G. Zhang;H. Lee;T. Rocheleau;R. ffrench-Constant;M. Jackson
狄氏剂和印防己毒素对 GABA(A) 受体单通道的调节。
DOI：
--
发表时间：
1998
期刊：
Neuroreport.
影响因子：
--
作者：
Ikeda,T;Nagata,K;Shono,T;Narahashi,T
通讯作者：
Narahashi,T
影响因子：
4.1
作者：
Hainzl, D;Cole, LM;Casida, JE
通讯作者：
Casida, JE
果蝇环二烯杀虫剂抗性基因的克隆：一种新的 GABAA 受体亚型？
DOI：
10.1016/0742-8413(93)90103-r
发表时间：
1993
期刊：
Comparative biochemistry and physiology. C, Comparative pharmacology and toxicology
影响因子：
--
作者：
Ffrench-Constant,RH
通讯作者：
Ffrench-Constant,RH