Partial lesion of dopamine neurons of rat substantia nigra impairs conditioned place aversion but spares conditioned place preference
| Autor: | Claudio Da Cunha, Donita L. Robinson, Peter Redgrave, Janaína K. Barbiero, Daniele C. Ramos, Laura N. Pulido, Bernardo F.C. Lima, Alexander Gómez-A |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
Male Substantia nigra Striatum 03 medical and health sciences chemistry.chemical_compound 0302 clinical medicine Reward Dopamine Neural Pathways medicine Animals Rats Wistar Oxidopamine Neurons Pars compacta General Neuroscience MPTP Dopaminergic Neurons Conditioned place preference Corpus Striatum Associative learning Substantia Nigra 030104 developmental biology nervous system chemistry 1-Methyl-4-phenyl-1 2 3 6-tetrahydropyridine Psychology Neuroscience 030217 neurology & neurosurgery medicine.drug |
| Zdroj: | Neuroscience. 349 |
| ISSN: | 1873-7544 |
| Popis: | Midbrain dopamine neurons play critical roles in reward- and aversion-driven associative learning. However, it is not clear whether they do this by a common mechanism or by separate mechanisms that can be dissociated. In the present study we addressed this question by testing whether a partial lesion of the dopamine neurons of the rat SNc has comparable effects on conditioned place preference (CPP) learning and conditioned place aversion (CPA) learning. Partial lesions of dopamine neurons in the rat substantia nigra pars compacta (SNc) induced by bilateral intranigral infusion of 6-hydroxydopamine (6-OHDA, 3μg/side) or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 200μg/side) impaired learning of conditioned place aversion (CPA) without affecting conditioned place preference (CPP) learning. Control experiments demonstrated that these lesions did not impair motor performance and did not alter the hedonic value of the sucrose and quinine. The number of dopamine neurons in the caudal part of the SNc positively correlated with the CPP scores of the 6-OHDA rats and negatively correlated with CPA scores of the SHAM rats. In addition, the CPA scores of the 6-OHDA rats positively correlated with the tissue content of striatal dopamine. Insomuch as reward-driven learning depends on an increase in dopamine release by nigral neurons, these findings show that this mechanism is functional even in rats with a partial lesion of the SNc. On the other hand, if aversion-driven learning depends on a reduction of extracellular dopamine in the striatum, the present study suggests that this mechanism is no longer functional after the partial SNc lesion. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect