Dataset Information

Knockdown of Nurr1 in the rat hippocampus: implications to spatial discrimination learning and memory.

ABSTRACT: Nurr1 expression is up-regulated in the brain following associative learning experiences, but its relevance to cognitive processes remains unclear. In these studies, rats initially received bilateral hippocampal infusions of control or antisense oligodeoxynucleotides (ODNs) 1 h prior to training in a holeboard spatial discrimination task. Such pre-training infusions of nurr1 antisense ODNs caused a moderate effect in learning the task and also impaired LTM tested 7 d later. In a second experiment, ODN infusions were given immediately after the animals had received two sessions of training, during which all animals showed normal learning. Although antisense treated rats were significantly impaired during the post-infusion stages of acquisition of the task, no group differences were observed during the LTM test given 7 d later. These animals were subjected 3 d later to reversal training in the same maze in the absence of any additional treatments. Remarkably, rats previously treated with antisense ODNs displayed perseveration: The animals were fixated with the previously learned pattern of baited holes, causing them to be significantly impaired in the extinction of acquired spatial preferences and future learning. We postulate that Nurr1 function in the hippocampus is important for normal cognitive processes.

SUBMITTER: Colon-Cesario WI

PROVIDER: S-EPMC1783627 | biostudies-literature | 2006 Nov-Dec

REPOSITORIES: biostudies-literature

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Knockdown of Nurr1 in the rat hippocampus: implications to spatial discrimination learning and memory.

Colón-Cesario Wanda I WI Martínez-Montemayor Michelle M MM Morales Sohaira S Félix Jahaira J Cruz Juan J Adorno Monique M Pereira Lixmar L Colón Nydia N Maldonado-Vlaar Carmen S CS Peña de Ortiz Sandra S

Learning & memory (Cold Spring Harbor, N.Y.) 20061101 6

Nurr1 expression is up-regulated in the brain following associative learning experiences, but its relevance to cognitive processes remains unclear. In these studies, rats initially received bilateral hippocampal infusions of control or antisense oligodeoxynucleotides (ODNs) 1 h prior to training in a holeboard spatial discrimination task. Such pre-training infusions of nurr1 antisense ODNs caused a moderate effect in learning the task and also impaired LTM tested 7 d later. In a second experimen ...[more]

PMID: 17142303

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Dataset Information

Knockdown of Nurr1 in the rat hippocampus: implications to spatial discrimination learning and memory.

Publications

Knockdown of Nurr1 in the rat hippocampus: implications to spatial discrimination learning and memory.

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