Zhou Miaomiao, Xia Huimin, Xu Younian, Xin Naixing, Liu Jiao, Zhang Shihai
Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
J Huazhong Univ Sci Technolog Med Sci. 2012 Jun;32(3):410-414. doi: 10.1007/s11596-012-0071-1. Epub 2012 Jun 9.
Although empirically well understood in their clinical administration, volatile anesthetics are not yet well comprehended in their mechanism studies. A major conundrum emerging from these studies is that there is no validated model to assess the presumed candidate sites of the anesthetics. We undertook this study to test the hypothesis that the single-celled Paramecium could be anesthetized and served as a model organism in the study of anesthetics. We assessed the motion of Paramecium cells with Expert Vision system and the chemoresponse of Paramecium cells with T-maze assays in the presence of four different volatile anesthetics, including isoflurane, sevoflurane, enflurane and ether. Each of those volatiles was dissolved in buffers to give drug concentrations equal to 0.8, 1.0, and 1.2 EC50, respectively, in clinical practice. We could see that after application of volatile anesthetics, the swimming of the Paramecium cells was accelerated and then suppressed, or even stopped eventually, and the index of the chemoresponse of the Paramecium cells (denoted as I ( che )) was decreased. All of the above impacts were found in a concentration-dependent fashion. The biphasic effects of the clinical concentrations of volatile anesthetics on Paramecium simulated the situation of high species in anesthesia, and the inhibition of the chemoresponse also indicated anesthetized. In conclusion, the findings in our studies suggested that the single-celled Paramecium could be anesthetized with clinical concentrations of volatile anesthetics and therefore be utilized as a model organism to study the mechanisms of volatile anesthetics.
尽管挥发性麻醉剂在临床应用中已被充分了解，但在其作用机制研究方面仍未被完全理解。这些研究中出现的一个主要难题是，尚无经过验证的模型来评估麻醉剂假定的作用位点。我们开展这项研究以检验单细胞草履虫可被麻醉并用作麻醉剂研究的模式生物这一假设。我们在存在四种不同挥发性麻醉剂（异氟烷、七氟烷、安氟烷和乙醚）的情况下，使用专家视觉系统评估草履虫细胞的运动，并通过T型迷宫试验评估草履虫细胞的化学感受性。在临床实践中，每种挥发性麻醉剂分别溶解于缓冲液中，使其药物浓度分别等于0.8、1.0和1.2 EC50。我们可以看到，应用挥发性麻醉剂后，草履虫细胞的游动先加速然后受到抑制，最终甚至停止，并且草履虫细胞的化学感受性指标（表示为I(che)）降低。上述所有影响均呈浓度依赖性。挥发性麻醉剂临床浓度对草履虫的双相作用模拟了麻醉中高度相似的情况，并且化学感受性的抑制也表明已被麻醉。总之，我们研究中的发现表明，单细胞草履虫可被临床浓度的挥发性麻醉剂麻醉，因此可作为研究挥发性麻醉剂作用机制的模式生物。
