Janisiewicz Agnieszka M, Jackson Orville, Firoz Elnaz F, Baxter Mark G
Department of Psychology, Harvard University, Cambridge, Massachusetts, USA.
Hippocampus. 2004;14(2):265-73. doi: 10.1002/hipo.10175.
Cholinergic medial septal neurons may regulate several aspects of hippocampal function, including place field stability and spatial working memory. Monkeys with damage to septal cholinergic neurons are impaired in visual-spatial conditional learning tasks; however, this candidate function of septal cholinergic neurons has not been studied extensively in the rat. In the present study, rats with selective lesions of cholinergic neurons in the medial septum and vertical limb of the diagonal band of Broca (MS/VDB), made with 192 IgG-saporin, were tested on a conditional associative learning task. In this task, which we term "environment-spatial" conditional learning, the correct location of a spatial response depended on the array of local environmental cues. MS/VDB-lesioned rats were impaired when the two parts of the conditional problem were presented concurrently, but not when one environment had been learned before the full conditional problem was presented. Our findings suggest that cholinergic MS/VDB neurons participate in some aspects of conditional associative learning in rats. They may also shed light on the involvement of cholinergic projections to the hippocampus in modulating and remodeling hippocampal spatial representations.
胆碱能内侧隔区神经元可能调节海马功能的多个方面，包括位置野稳定性和空间工作记忆。内侧隔区胆碱能神经元受损的猴子在视觉空间条件学习任务中表现受损；然而，内侧隔区胆碱能神经元的这一潜在功能在大鼠中尚未得到广泛研究。在本研究中，用192IgG-皂草素对内侧隔区和布罗卡斜角带垂直支（MS/VDB）中的胆碱能神经元进行选择性损伤的大鼠，接受了一项条件性联想学习任务测试。在这个我们称为“环境-空间”条件学习的任务中，空间反应的正确位置取决于局部环境线索的排列。当条件问题的两个部分同时呈现时，MS/VDB损伤的大鼠表现受损，但当在完整条件问题呈现之前已经学习了一个环境时则不然。我们的研究结果表明，胆碱能MS/VDB神经元参与大鼠条件性联想学习的某些方面。它们也可能有助于阐明胆碱能投射到海马在调节和重塑海马空间表征中的作用。
