Pussinen R, Nieminen S, Koivisto E, Haapalinna A, Riekkinen P, Sirvio J
A.I. Virtanen Institute, University of Kuopio, Finland.
Neurobiol Learn Mem. 1997 Jan;67(1):69-74. doi: 10.1006/nlme.1996.3738.
The aim of the present study was to investigate whether the activation of alpha-1 adrenergic receptors can influence intermediate-term memory. Therefore, the effects of ST 587 (30 or 100 micrograms/kg), a putative alpha-1 agonist, on the retention of the radial arm task using non-matching to sample with a 4-h delay were investigated in rats. The results indicated that the administration of ST 587 (100 micrograms/kg) before a sampling phase increased the time to complete the sampling phase which was due to an increased number of errors of repetition (regarded as working memory errors) and a reduced number of arms visited in a given time (regarded as behavioral activity). However, this treatment increased the number of correct choices before the first error during the retention phase in this task. Since we were also interested in investigating the role of NMDA receptors in memory encoding, we investigated whether NMDA receptor modulation by d-cycloserine (1 or 10 mg/kg), a partial agonist of the glycine site on the NMDA receptor, had any influence on the performance of rats in this task. The results indicated that d-cycloserine (10 mg/kg) given before the sampling phase did not influence the performance of rats during the sampling phase, but it did improve their choice accuracy during the retention phase of this task. These data suggest that the systemic administration of either an alpha-1 agonist or an indirect agonist of NMDA receptors can facilitate intermediate-term retention of spatial information.
本研究的目的是调查α-1肾上腺素能受体的激活是否会影响中期记忆。因此，在大鼠中研究了假定的α-1激动剂ST 587（30或100微克/千克）对采用延迟4小时的非匹配样本的放射状臂任务保持力的影响。结果表明，在取样阶段之前给予ST 587（100微克/千克）会增加完成取样阶段的时间，这是由于重复错误（视为工作记忆错误）数量增加以及在给定时间内访问的臂数减少（视为行为活动）。然而，这种处理增加了该任务保持阶段首次出现错误之前的正确选择数量。由于我们也对研究NMDA受体在记忆编码中的作用感兴趣，我们研究了NMDA受体的甘氨酸位点部分激动剂d-环丝氨酸（1或10毫克/千克）对大鼠在此任务中的表现是否有任何影响。结果表明，在取样阶段之前给予d-环丝氨酸（10毫克/千克）不会影响大鼠在取样阶段的表现，但确实提高了它们在该任务保持阶段的选择准确性。这些数据表明，全身给予α-1激动剂或NMDA受体间接激动剂均可促进空间信息的中期保持。
