Effects of Activation and Blockade of Dopamine Receptors on the Extinction of a Passive Avoidance Reaction in Mice with a Depressive-Like State

• Published in: Neuroscience and behavioral physiology 2010, Vol.40 (1), p.55-59
• Main Authors: Dubrovina, N. I., Zinov’eva, D. V.
• Format: Article
• Language: English
• Subjects: 2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benzazepine - pharmacology; Animals; Avoidance Learning - drug effects; Avoidance Learning - physiology; Behavioral Sciences; Benzazepines - pharmacology; Biomedical and Life Sciences; Biomedicine; Conditioning, Classical - drug effects; Conditioning, Classical - physiology; Darkness; Depression - physiopathology; Dopamine; Dopamine Agonists - pharmacology; Dopamine Antagonists - pharmacology; Dopamine D2 Receptor Antagonists; Extinction; Extinction, Psychological - drug effects; Extinction, Psychological - physiology; Ligands; Male; Medical research; Memory; Mice; Mice, Inbred C57BL; Neurobiology; Neuropsychological Tests; Neurosciences; Physiology; Quinpirole - pharmacology; Receptors, Dopamine D1 - agonists; Receptors, Dopamine D1 - antagonists & inhibitors; Receptors, Dopamine D1 - metabolism; Receptors, Dopamine D2 - agonists; Receptors, Dopamine D2 - metabolism; Sulpiride - pharmacology; Variance analysis
• ISSN: 0097-0549; 1573-899X
• DOI: 10.1007/s11055-009-9226-3

Learning and extinction of a conditioned passive avoidance reaction resulting from neuropharmacological actions on dopamine D 1 and D 2 receptors were demonstrated to be specific in intact mice and in mice with a depressive-like state. Learning was degraded only after administration of the D 2 receptor antagonist sulpiride and was independent of the initial functional state of the mice. In intact mice, activation of D 2 receptors with quinpirole led to a deficit of extinction, consisting of a reduction in the ability to acquire new inhibitory learning in conditions associated with the disappearance of the expected punishment. In mice with the “behavioral despair” reaction, characterized by delayed extinction, activation of D 1 receptors with SKF38393 normalized this process, while the D 2 agonist was ineffective. A positive effect consisting of accelerated extinction of the memory of fear of the dark (“dangerous”) sector of the experimental chamber was also seen on blockade of both types of dopamine receptor.