Department of Anesthesia and Perioperative Care, University of California, San Francisco, CA 94143-0464, USA.
Anesth Analg. 2010 Jan 1;110(1):59-63. doi: 10.1213/ANE.0b013e3181c4bc69. Epub 2009 Nov 21.
A prokaryotic member of the gamma-aminobutyric acid type A receptor superfamily (GLIC) was recently cloned from the cyanobacterium Gloeobacter violaceus, its function characterized, and its 3-dimensional x-ray diffraction crystal structure determined. We report its modulation by 9 anesthetics using 2-electrode voltage clamping in Xenopus laevis oocytes. Desflurane, halothane, isoflurane, sevoflurane, and propofol inhibited currents through GLIC at and below concentrations used clinically. Hill numbers averaged 0.3, indicating negative cooperativity or multiple sites or mechanisms of action. A 2-site model fit the data for desflurane and halothane better than a 1-site model. Xenon and etomidate modulated GLIC at or above clinical concentrations, with no cooperativity. Ethanol and nitrous oxide did not modulate GLIC at surgical anesthetic concentrations. These investigations lay the groundwork for further structural and functional studies of anesthetic actions on GLIC.
最近从蓝细菌（Gloeobacter violaceus）中克隆出一种γ-氨基丁酸 A 型受体超家族（GLIC）的原核成员，对其功能进行了表征，并确定了其三维 X 射线衍射晶体结构。我们使用 Xenopus laevis 卵母细胞中的 2 电极电压钳技术报告了其对 9 种麻醉剂的调制。地氟烷、氟烷、异氟烷、七氟烷和丙泊酚在临床使用浓度及以下浓度时抑制 GLIC 电流。Hill 数平均为 0.3，表明存在负协同作用或多个作用位点或机制。对于地氟烷和氟烷，双位点模型比单一位点模型更适合数据拟合。氙气和依托咪酯在临床浓度或以上调节 GLIC，没有协同作用。乙醇和一氧化二氮在手术麻醉浓度下不调节 GLIC。这些研究为进一步研究麻醉剂对 GLIC 的作用的结构和功能奠定了基础。
