Distribution of dopamine D(2)-like receptors in the rat amygdala and their role in the modulation of unconditioned fear and anxiety
| Autor: | Andrea Gallegos-Cari, Anita C. Hansson, Kjell Fuxe, Minerva Crespo-Ramírez, M. Pérez de la Mora, Daniel Marcellino |
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| Rok vydání: | 2011 |
| Předmět: |
Male
Immunocytochemistry In situ hybridization Anxiety Amygdala Dopamine Conditioning Psychological medicine Animals RNA Messenger Rats Wistar Receptor Maze Learning Raclopride Analysis of Variance Electroshock Dose-Response Relationship Drug Receptors Dopamine D2 General Neuroscience Receptors Dopamine D3 Fear Rats medicine.anatomical_structure nervous system Gene Expression Regulation Exploratory Behavior Autoradiography Dopamine Antagonists Psychology Sulpiride Neuroscience Nucleus medicine.drug |
| Zdroj: | Neuroscience. 201 |
| ISSN: | 1873-7544 |
| Popis: | Amygdaloid dopamine D(2) receptors play an important role in the modulation of fear/anxiety. Their topographical distribution within the amygdala is however unclear, and their role in unconditioned fear/anxiety remains largely unknown. The aim of this paper was to study the intra-amygdaloid distribution of D(2) receptors and to ascertain their role in unconditioned anxiety. Chemical anatomical studies in the rat, using D(2) and D(3)in situ hybridization, quantitative receptor autoradiography with either [(3)H]raclopride or [(125)I]sulpiride, and D(2)-like immunocytochemistry showed that the highest density of dopamine D(2) receptors is present in the central amygdaloid nucleus, particularly within its latero-capsular division, in which a D(2) but not a D(3) mRNA signal was observed. However, although at considerably reduced densities dopamine D(2) receptors were also found in other locations within the amygdala, including the basolateral nucleus. Behaviorally, the infusion of raclopride (0.75-4 μg/side) in the area of the central amygdaloid nucleus resulted at low doses in the appearance of anxiogenic-like effects in the Shock-Probe Burying test, whereas no effects of raclopride treatment were found at any dose in the Elevated Plus-Maze and the Open-Field test. Our results indicate that amygdaloid dopamine D(2)-like receptors have a topographically differentiated distribution within the rat amygdala, the major location being in the central amygdaloid nucleus. D(2)-like receptors play a role in the modulation of anxiety responses involving a potential differential function of D(2)-like receptors in the central amygdaloid nucleus versus the basolateral amygdaloid nucleus. |
| Databáze: | OpenAIRE |
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