NMR study of volatile anesthetic binding to nicotinic acetylcholine receptors.
NMR study of volatile anesthetic binding to nicotinic acetylcholine receptors.
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挥发性麻醉剂与烟碱乙酰胆碱受体结合的核磁共振研究。
DOI：
10.1016/s0006-3495(00)76632-x
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发表时间：
2000
影响因子：
3.4
通讯作者：
Firestone,L
中科院分区：
文献类型：
--
作者：
Xu,Y;Seto,T;Tang,P;Firestone,L
新的证据表明，挥发性麻醉剂与蛋白质特异性相互作用。然而，直接结合分析在很大程度上限于可溶性蛋白质。本研究采用19 F核磁共振波谱和气相色谱法研究了异氟醚（一种临床上重要的挥发性麻醉剂）与电鳐（Torpedo electroplax）膜结合烟碱乙酰胆碱受体（nAChRs）之间的特异性相互作用。将受体重组到1，2-二油酰-sn-甘油-3-磷酸胆碱（DOPC）脂质囊泡中。在对非特异性分配到脂质中进行校正后，发现在15°C下异氟烷与nAChR结合的平衡解离常数Kd为0.36±0.03mM。该值在药物的临床相关浓度范围内。基于通过二喹啉甲酸法测定的囊泡悬浮液中的受体浓度和通过气相色谱法测定的结合异氟烷分数Xb，可以估计每个受体平均有9-10个特异性结合的异氟烷分子，或每个亚基有2个。结合后，异氟烷19 F共振的横向弛豫时间常数（T2）降低了近三个数量级，表明特异性结合异氟烷的迁移率急剧降低。动力学分析显示结合的解离速率k−1为1.7× 104 s −1。因此，其导通速率k+1可以计算为104.8 × 107 M − 1 s −1，这表明这是一种几乎是扩散受限的缔合。这与麻醉剂与可溶性蛋白质牛血清白蛋白（BSA）的结合相反，其中k +1和k − 1至少慢一个数量级。它的结论是，脂质的存在下，挥发性麻醉药和神经元受体之间的结合动力学的正确评价可能是至关重要的。
New lines of evidence suggest that volatile anesthetics interact specifically with proteins. Direct binding analysis, however, has been largely limited to soluble proteins. In this study, specific interaction was investigated between isoflurane, a clinically important volatile anesthetic, and membrane-bound nicotinic acetylcholine receptors (nAChRs) fromTorpedo electroplax, using19F nuclear magnetic resonance spectroscopy and gas chromatography. The receptors were reconstituted into 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) lipid vesicles. After correcting for nonspecific partitioning into the lipid, the equilibrium dissociation constant,Kd, of isoflurane binding to nAChR at 15°C was found to be 0.36±0.03mM. This value is within the clinically relevant concentration range of the agent. Based on the receptor concentrations in the vesicle suspension assayed by the bicinchoninic acid method and the fraction of bound isoflurane, Xb, determined by gas chromatography, an estimate of an average of 9–10 specifically bound isoflurane molecules can be made for each receptor, or two for each subunit. Upon binding, the transverse relaxation time constant (T2) of19F resonance of isoflurane is decreased by nearly three orders of magnitude, indicating a dramatic reduction in the mobility of specifically bound isoflurane. Kinetic analysis reveals that the off rate of binding,k−1, is 1.7×104s−1. The on rate,k+1, can thus be calculated to be ∼4.8×107M−1s−1, suggesting a nearly diffusion-limited association. This is in contrast to anesthetic binding to a soluble protein, bovine serum albumin (BSA), wherek+1andk−1are at least an order of magnitude slower. It is concluded that the presence of lipids may be critical for the correct evaluation of binding kinetics between volatile anesthetics and neuronal receptors.
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影响因子：
3.6
作者：
S. Forman;K. Miller;G. Yellen
通讯作者：
S. Forman;K. Miller;G. Yellen
通过麻醉剂和非麻醉剂的联合使用揭示麻醉作用部位的统一特征。
影响因子：
3.5
作者：
Xu,Y;Tang,P;Liachenko,S
通讯作者：
Liachenko,S
用于全身麻醉作用的两亲位点？
DOI：
10.1016/s0005-2736(96)00184-8
发表时间：
1997
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
Xu,Y;Tang,P
通讯作者：
Tang,P
异氟烷与牛血清白蛋白立体选择性结合的 19F 核磁共振研究。
影响因子：
3.4
作者：
Xu,Y;Tang,P;Firestone,L;Zhang,TT
通讯作者：
Zhang,TT
麻醉剂和非固定剂与短杆菌肽 A 通道相互作用的结构后果。
影响因子：
3.4
作者：
Tang,P;Simplaceanu,V;Xu,Y
通讯作者：
Xu,Y