Characterization of the effects of omega-conotoxin GVIA on the responses of voltage-sensitive calcium channels.
Characterization of the effects of omega-conotoxin GVIA on the responses of voltage-sensitive calcium channels.
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表征 omega-芋螺毒素 GVIA 对电压敏感钙通道反应的影响。
DOI：
10.1111/j.1474-8673.1989.tb00215.x
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
A. Salama
中科院分区：
文献类型：
--
作者：
R. Keith;T. Mangano;M. Pacheco;A. Salama
1. omega- concontoxin GVIA （omega-CT）对K+诱导的皮质脑切片[3H]-去甲肾上腺素释放有有效的抑制作用（IC50约为2nM），但低于最大抑制作用（55%）。在0.1微米时，omega-CT抑制[3H] γ -氨基丁酸（GABA）和[3H]-乙酰胆碱释放约40%。2. K+诱导的[3H]-去甲肾上腺素释放也与PN 200-110（二氢吡啶L通道拮抗剂）、BAY K8644 （L通道VSCC激动剂）和Cd++（无机L-和n通道拮抗剂）的作用有关。10 μ m Cd++和1 μ m PN 200-110对K+诱发的[3H]-去甲肾上腺素释放分别抑制52%和17%。10 microM Bay k8644可使K+诱发的[3H]-去甲肾上腺素释放增加22%，而这种增强作用被1 microM pn200 -110阻断。3. omega-CT对大鼠输精管（IC50约为10 nM）和豚鼠回肠（IC50约为60 nM）的电诱发抽搐反应产生了近乎最大的抑制作用，但对去甲肾上腺素（输精管）或卡巴酚（回肠）的节后收缩反应没有影响。当浓度高达1微米时，omega-CT对K+诱导的大鼠主动脉收缩没有影响。4. omega-CT（0.1微米）既没有改变[3H]-(+)- pn 200-110的平衡结合，也没有改变替帕米或地尔硫卓对[3H]-(+)- pn 200-110结合的变构调节。5. 这些观察结果支持了n型电压敏感钙通道在神经元兴奋与神经递质释放耦合中起主要作用的观点。
1. omega-conotoxin GVIA (omega-CT) caused a potent (IC50 approximately 2nM) but less than maximal (55%) inhibition of [3H]-noradrenaline release from cortical brain slices induced by K+. At 0.1 microM, omega-CT inhibited [3H] gamma-aminobutyric acid (GABA) and [3H]-acetylcholine release by approximately 40%. 2. K+-evoked [3H]-noradrenaline release from cortical brain slices was also characterized with respect to the effects of PN 200-110 (dihydropyridine L-channel antagonist), BAY K8644 (L-channel VSCC agonist), and Cd++ (an inorganic L- and N-channel antagonist). 10 microM Cd++ and 1 microM PN 200-110 inhibited K+-evoked [3H]-noradrenaline release by 52% and 17%, respectively. 10 microM Bay K 8644 enhanced K+-evoked [3H]-noradrenaline release by 22%, and this enhancement was blocked by 1 microM PN 200-110. 3. omega-CT caused a near-maximal inhibition of the electrically evoked twitch responses of the rat vas deferens (IC50 approximately 10 nM) and guinea-pig ileum (IC50 approximately 60 nM), but had no effect on the postjunctional contractile responses of noradrenaline (vas deferens) or carbachol (ileum). At concentrations as high as 1 microM, omega-CT had no effect on the K+-induced contraction of the rat aorta. 4. Neither the equilibrium binding of [3H]-(+)-PN 200-110 nor the allosteric regulation of [3H]-(+)-PN 200-110 binding by tiapamil or diltiazem were altered by omega-CT (0.1 microM). 5. These observations support the notion that the N-type voltage-sensitive calcium channel plays a major role in coupling neuronal excitation with neurotransmitter release.
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DOI：
10.1126/science.2425434
发表时间：
1986
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Sturek,M;Hermsmeyer,K
通讯作者：
Hermsmeyer,K
二氢吡啶敏感脑钙通道的α亚基的鉴定。
DOI：
10.1126/science.2436296
发表时间：
1987
期刊：
Science (New York, N.Y.)
影响因子：
--
作者：
Takahashi,M;Catterall,WA
通讯作者：
Catterall,WA
影响因子：
2.9
作者：
OLIVERA, BM;CRUZ, LJ;RIVIER, J
通讯作者：
RIVIER, J
心脏组织中二氢吡啶敏感的电压依赖性钙通道的纯化和表征。
DOI：
--
发表时间：
1987
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Cooper,CL;Vandaele,S;Barhanin,J;Fosset,M;Lazdunski,M;Hosey,MM
通讯作者：
Hosey,MM
影响因子：
56.9
作者：
MILLER, RJ
通讯作者：
MILLER, RJ