Aranda Lourdes, Begega Azucena, Sánchez-López Jorge, Aguirre José A, Arias Jorge L, Santín Luis J
Dpto. Psicobiología y Metodología de las CC, Universidad de Málaga, Spain.
Physiol Behav. 2008 Jun 9;94(3):322-30. doi: 10.1016/j.physbeh.2008.01.024. Epub 2008 Feb 9.
The aim of our study was to examine the supramammillary (SuM) area involvement in spatial memory. Sprague-Dawley rats with chronically implanted cannula in the supramammillary area were trained in two spatial memory tasks with different memory demands: reference and working memory. In the spatial reference memory task, the rats received microinjections in the SuM area of tetrodotoxin (TTX) (0.5 ng diluted in 0.5 microL of saline) or saline (0.5 microL). The microinjections were administered 30 min before the spatial training (day 4) (to assess the effect on acquisition) and on the following two days (days 5 and 6) the training was conducted without microinjections (to study the effect on consolidation). On the last training day (day 7), in order to assess the retrieval of spatial information, the rats received the microinjections 30 min before the spatial training. The spatial working memory used was a delayed-matching-to-position (DMTP) task. Spatial training was performed for seven days. During the first three days of the spatial training, the rats achieved a good spatial knowledge and learnt the working memory rule necessary to solve the spatial task. On days 4 and 6, the rats received microinjections to study involvement of the SuM area in working memory. The results showed that temporary inactivation of SuM area impairs both the rat's ability to solve a spatial working memory task with DMTP demands and the recovery of spatial information in a spatial reference memory task. We suggest that SuM area is involved in the rearrangement of spatial information during spatial working memory tasks with DMTP memory demands.
我们研究的目的是检测乳头体上区（SuM）在空间记忆中的参与情况。在乳头体上区长期植入套管的Sprague-Dawley大鼠接受了两种具有不同记忆需求的空间记忆任务训练：参考记忆和工作记忆。在空间参考记忆任务中，大鼠在乳头体上区接受微量注射河豚毒素（TTX）（0.5纳克，用0.5微升生理盐水稀释）或生理盐水（0.5微升）。在空间训练前30分钟（第4天）进行微量注射（以评估对习得的影响），在接下来的两天（第5天和第6天），在不进行微量注射的情况下进行训练（以研究对巩固的影响）。在最后一个训练日（第7天），为了评估空间信息的提取，在空间训练前30分钟给大鼠进行微量注射。所使用的空间工作记忆是延迟位置匹配（DMTP）任务。空间训练持续七天。在空间训练的前三天，大鼠获得了良好的空间知识，并学会了解决空间任务所需的工作记忆规则。在第4天和第6天，给大鼠进行微量注射，以研究乳头体上区在工作记忆中的参与情况。结果表明，乳头体上区的暂时失活会损害大鼠解决具有DMTP要求的空间工作记忆任务的能力以及在空间参考记忆任务中空间信息的恢复。我们认为，在具有DMTP记忆需求的空间工作记忆任务中，乳头体上区参与了空间信息的重新排列。
