Dopamine D3 Receptors Inhibit Hippocampal Gamma Oscillations by Disturbing CA3 Pyramidal Cell Firing Synchrony

Cortical gamma oscillations are associated with cognitive processes and are altered in several neuropsychiatric conditions such as schizophrenia and Alzheimer’s disease. Since dopamine D3 receptors are possible targets in treatment of these conditions, it is of great importance to understand their role in modulation of gamma oscillations. The effect of D3 receptors on gamma oscillations and the underlying cellular mechanisms were investigated by extracellular local field potential and simultaneous intracellular sharp micro-electrode recordings in the CA3 region of the hippocampus in vitro. D3 receptors decreased the power and broadened the bandwidth of gamma oscillations induced by acetylcholine or kainate. Blockade of the D3 receptors resulted in faster synchronization of the oscillations, suggesting that endogenous dopamine in the hippocampus slows down the dynamics of gamma oscillations by activation of D3 receptors. Investigating the underlying cellular mechanisms for these effects showed that D3 receptor activation decreased the rate of action potentials (APs) during gamma oscillations and reduced the precision of the AP phase coupling to the gamma cycle in CA3 pyramidal cells. The results may offer an explanation how selective activation of D3 receptors may impair cognition and how, in converse, D3 antagonists may exert pro-cognitive and antipsychotic effects

Europa. Central. 1:2020200

Coordenadas E7 40'-E20 40'/N55 10'-N50 09'. Meridiano de ParísEscala gráfica además en leguas marinas y millas de Prusi

Francia. 1:2539680

Coordenadas : E6 20'-O5 00'/N56 55'-N42 25'. Meridiano de ParísRelieve : líneas perpendiculares normalesInserta mapa de CórcegaAl márgen inferior izquierdo : Pous les détails orographiques voir la France Phisique de L'Atla

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Marca el itinerario de los aliados con las sucesivas acampadas en los diferentes diasMarca el itinerario del servicio topográficoInserta mapa indice de la expediciónInserta mapa de las defensas de Pei - Ho y lugar de desembarcoCon : Expedition du Mexique 1861 - - Expeditión de Crimee 1854 - - Conchinchine Francaise expedition 1858 60

Italia. 1:102040

Coordenadas : E4 10'-E10 10'/N47 15'-N43 40'. Meridiano de ParísRelieve sombreadoInserta [mapa del golfo de Venecia y Territorios adyacentes]. - Escala 1:20408

AFRICA. S. Mapas generales (1872). 1:14305155

Coordenadas (E103 10'-E105 10'/N11 40'-N10 10'). Referidas al meridiano de ParísInserta: "Mapa de la isla de Pould Condore"Con: Expeditión de Crimée ; Expedition de Chine ; Expexpedition du Mexiqu

MEXICO. SE. 1:200000

Coloreado el itinerario del ejércitoInserta : Perfil du TerreinRelieve : sombread

Argel (Argelia). Mapas generales. 1870 (1830-1858). 1:500000

Relieve representado por sombreadoAlgerie ; Ora

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Relieve : sombreadoCon : Algerue - - Environs d'Alge

CRIMEA (Ucrania) (Península). Geografía militar. 1870 (1854-1855). 113378

En color rojo líneas de itinerario del ejército aliadoRelieve : sombreadoCon : Conchinchine Francaise, expedition de 1858 - - Expedition de Chine 1860 - - Expedition du Mexique 186