Sparkman Nathan L, Kohman Rachel A, Scott Vincent J, Boehm Gary W
Department of Psychology, Texas Christian University, Fort Worth, 76129, USA.
Physiol Behav. 2005 Sep 15;86(1-2):244-51. doi: 10.1016/j.physbeh.2005.07.016.
Several studies report that lipopolysaccharide (LPS) or interleukin-1beta (IL-1beta) may affect behavior in a variety of learning tasks, including the Morris water maze (MWM), though the nature of these effects varies with testing parameters. The present study used C57BL/6J mice to evaluate the effect of a single intraperitoneal LPS injection 4 h prior to day 1 of testing, LPS before each day of testing, or saline prior to each test day, on performance in two variations of the MWM. In the first experiment, one that utilized a standard hidden platform, LPS clearly affected performance, as shown by increased latencies and greatly decreased swimming speeds. However, a modest effect on distance swam was only present during later test days. These data show a clear deficit in performance (driven by decreased swim speed), and some evidence for learning decrements on later test days. To explore to what degree the effects of LPS in the water maze were the result of alterations in performance factors such as motor behavior, a second experiment was conducted in which a highly visible jet-black platform was utilized. Despite eliminating the need for spatial learning, mice administered LPS still exhibited significantly increased latency scores and decreased swim speed. However, there was no difference between treatment groups in distance swam. These results reinforce the idea that, even when present, potential learning effects of LPS may sometimes be difficult to untangle from performance effects unrelated to learning, and underscore the need for utilizing behavioral tests that offer suitable control for LPS-induced performance effects.
多项研究报告称，脂多糖（LPS）或白细胞介素-1β（IL-1β）可能会影响多种学习任务中的行为，包括莫里斯水迷宫（MWM），尽管这些影响的性质会因测试参数而异。本研究使用C57BL/6J小鼠来评估在测试第1天前4小时单次腹腔注射LPS、在每天测试前注射LPS或在每个测试日前注射生理盐水对MWM两种变体表现的影响。在第一个实验中，即使用标准隐藏平台的实验，LPS明显影响了表现，表现为潜伏期延长和游泳速度大幅下降。然而，对游泳距离的适度影响仅在后期测试日出现。这些数据显示出明显的表现缺陷（由游泳速度下降驱动），以及后期测试日学习能力下降的一些证据。为了探究LPS在水迷宫中的影响在多大程度上是运动行为等表现因素改变的结果，进行了第二个实验，其中使用了一个非常显眼的 jet - black平台。尽管无需进行空间学习，但注射LPS的小鼠仍表现出潜伏期得分显著增加和游泳速度下降。然而，各治疗组在游泳距离上没有差异。这些结果强化了这样一种观点，即即使存在，LPS的潜在学习影响有时可能难以与与学习无关的表现影响区分开来，并强调需要利用能够为LPS诱导的表现影响提供适当对照的行为测试。
