Keil R L, Wolfe D, Reiner T, Peterson C J, Riley J L
Department of Biochemistry and Molecular Biology, Milton S. Hershey Medical Center, Pennsylvania State University, Hershey, 17033, USA.
Mol Cell Biol. 1996 Jul;16(7):3446-53. doi: 10.1128/MCB.16.7.3446.
The mechanism(s) and site(s) of action of volatile inhaled anesthetics are unknown in spite of the clinical use of these agents for more than 150 years. In the present study, the model eukaryote Saccharomyces cerevisiae was used to investigate the action of anesthetic agents because of its powerful molecular genetics. It was found that growth of yeast cells is inhibited by the five common volatile anesthetics tested (isoflurane, halothane, enflurane, sevoflurane, and methoxyflurane). Growth inhibition by the agents is relatively rapid and reversible. The potency of these compounds as yeast growth inhibitors directly correlates with their lipophilicity as is predicted by the Meyer-Overton relationship, which directly correlates anesthetic potency of agents and their lipophilicity. The effects of isoflurane on yeast cells were characterized in the most detail. Yeast cells survive at least 48 h in a concentration of isoflurane that inhibits colony formation. Mutants resistant to the growth-inhibitory effects of isoflurane are readily selected. The gene identified by one of these mutations, zzz4-1, has been cloned and characterized. The predicted ZZZ4 gene product has extensive homology to phospholipase A2-activating protein, a GO effector protein of mice. Both zzz4-1 and a deletion of ZZZ4 confer resistance to all five of the agents tested, suggesting that signal transduction may be involved in the response of these cells to volatile anesthetics.
尽管挥发性吸入麻醉剂已临床使用超过150年，但其作用机制和作用位点仍不清楚。在本研究中，由于其强大的分子遗传学特性，真核模式生物酿酒酵母被用于研究麻醉剂的作用。结果发现，所测试的五种常见挥发性麻醉剂（异氟烷、氟烷、恩氟烷、七氟烷和甲氧氟烷）均可抑制酵母细胞的生长。这些药剂对生长的抑制作用相对迅速且可逆。正如迈耶-奥弗顿关系所预测的那样，这些化合物作为酵母生长抑制剂的效力与其亲脂性直接相关，而迈耶-奥弗顿关系直接将药剂的麻醉效力与其亲脂性联系起来。对异氟烷对酵母细胞的影响进行了最详细的表征。酵母细胞在抑制菌落形成的异氟烷浓度下至少存活48小时。对异氟烷生长抑制作用具有抗性的突变体很容易被筛选出来。其中一个突变所鉴定的基因zzz4 - 1已被克隆并进行了表征。预测的ZZZ4基因产物与磷脂酶A2激活蛋白具有广泛的同源性，磷脂酶A2激活蛋白是小鼠的一种GO效应蛋白。zzz4 - 1和ZZZ4的缺失均赋予了对所有五种测试药剂的抗性，这表明信号转导可能参与了这些细胞对挥发性麻醉剂的反应。
