Studies on the long-term effects of general anesthetics on the learning ability of aged rats

据报道，异氟醚，一种吸入性全身麻醉剂，在动物从麻醉中醒来数周后，会损害大鼠的空间学习能力。在这项研究中，我们检验了以下假设：(1)异氟醚影响年轻成年大鼠麻醉后的空间学习；(2)如果在夜间大鼠更活跃的时候进行麻醉，这种影响会更明显。将大鼠分为4组(1)白天用1.2%异氟醚麻醉2小时；(2)白天不麻醉但与(1)相同处理；(3)夜间用1.2%异氟醚麻醉2小时；(4)不麻醉但与(4)相同处理。8臂径向迷宫试验于麻醉或处理后2天开始，持续21天。这四组大鼠在该测试的任何测量参数上都没有差异，比如学习迷宫所需的天数。我们得出结论，异氟醚不会影响年轻成年大鼠麻醉后的空间学习能力，无论麻醉是在白天还是夜间进行。

It has been reported that isoflurane, an inhalational general anesthetic, impairs spatial learning in rats weeks after the animals wake up from anesthesia. In this study, we tested the hypotheses that (1) isoflurane affects spatial learning after anesthesia in young adult rats, and that (2) this effect is more pronounced if anesthesia is performed during the night time while the rat is more active.The rats were divided into 4 groups (1) isoflurane 1.2% for 2 hours during the day time, (2) no anesthesia but otherwise handled identically as in (1) during the day time, (3) isoflurane 1.2% for 2 hours during the night time, (4) no anesthesia but otherwise handled identically as in (4). The 8-arm radial maze test was started 2 days after anesthesia or handling and continued for 21 days. These 4 groups of rats did not differ in any of the measured paremeters for this test, such as the number of days required to learn the maze. We conclude that isoflurane does NOT affect spatial learning ability after anesthesia in young adult rat, irrespective of whether anesthesia was administered during the day or night.