Neurotransmitter release during delay eyeblink classical conditioning: Role of norepinephrine in consolidation and effect of age
| Autor: | A. Schlunck, A. George, Paula C. Bickford, M.C. Cartford, Amy Samec, M. Avilas, Daniel Paredes, Briony J. Catlow, Brent J. Small |
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| Rok vydání: | 2009 |
| Předmět: |
Male
Aging Cerebellum Time Factors Cognitive Neuroscience Adrenergic beta-Antagonists education Glutamic Acid Experimental and Cognitive Psychology Article gamma-Aminobutyric acid Norepinephrine Behavioral Neuroscience chemistry.chemical_compound Memory Receptors Adrenergic beta medicine Animals Neurotransmitter gamma-Aminobutyric Acid Neurotransmitter Agents Glutamate receptor Association Learning Classical conditioning Propranolol Conditioning Eyelid Rats Inbred F344 Rats Associative learning medicine.anatomical_structure Eyeblink conditioning chemistry Cerebellar cortex Extracellular Space Psychology Neuroscience medicine.drug |
| Zdroj: | Neurobiology of Learning and Memory. 92:267-282 |
| ISSN: | 1074-7427 |
| DOI: | 10.1016/j.nlm.2008.08.008 |
| Popis: | Delay classical eyeblink conditioning (EBC) is an important model of associative, cerebellar-dependent learning. Norepinephrine (NE) plays a significant modulatory role in the acquisition of learning; however, other neurotransmitters are also involved. The goal was to determine whether NE, gamma-aminobutyric acid (GABA) and glutamate (GLU) release are observed in cerebellar cortex during EBC, and whether such release was selectively associated with training. Further studies examined the role of the β-noradrenergic receptor in consolidation of the learned response by local infusion of propranolol at 5–120 min following training into the cerebellar cortex. In vivo microdialysis coupled to EBC was performed to examine neurotransmitter release. An increase in the extracellular level of NE was observed during EBC and was maximal on day 1 and diminished in amplitude with subsequent days of training. No changes in baseline NE release were observed in pseudoconditioning indicating that NE release is directly related to the associative learning process. The extracellular levels of GABA were also increased selectively during paired training however, the magnitude of GABA release increased over days of training. GLU release was observed to increase during both paired and unpaired training, suggesting that learning does not occur prior to the information arriving in the cerebellum. When propranolol was administered at either 5-, 60-, or 120-min post-training, there was an inhibition of conditioned responses, these data support the hypothesis that NE is important for consolidation of learning. In another set of experiments we demonstrate that the timing of release of NE, GABA and glutamate are significantly delayed in onset and lengthened in duration in the 22-month-old F344 rats. Over days of training the timing of release becomes closer to the timing of training and this is associated with increased learning of conditioned responses in the aged rats. |
| Databáze: | OpenAIRE |
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