Miguéns Miguel, Kastanauskaite Asta, Coria Santiago M, Selvas Abraham, Ballesteros-Yañez Inmaculada, DeFelipe Javier, Ambrosio Emilio
Departamento de Psicología Básica I, Facultad de Psicología, Universidad Nacional de Educación a Distancia (UNED), C/ Juan del Rosal n° 10, Madrid 28040, Spain Laboratorio Cajal de Circuitos Corticales (CTB), Universidad Politécnica de Madrid, Pozuelo de Alarcón, Madrid 28223, Spain.
Laboratorio Cajal de Circuitos Corticales (CTB), Universidad Politécnica de Madrid, Pozuelo de Alarcón, Madrid 28223, Spain.
Cereb Cortex. 2015 Jan;25(1):56-65. doi: 10.1093/cercor/bht200. Epub 2013 Aug 21.
Chronic exposure to cocaine induces modifications to neurons in the brain regions involved in addiction. Hence, we evaluated cocaine-induced changes in the hippocampal CA1 field in Fischer 344 (F344) and Lewis (LEW) rats, 2 strains that have been widely used to study genetic predisposition to drug addiction, by combining intracellular Lucifer yellow injection with confocal microscopy reconstruction of labeled neurons. Specifically, we examined the effects of cocaine self-administration on the structure, size, and branching complexity of the apical dendrites of CA1 pyramidal neurons. In addition, we quantified spine density in the collaterals of the apical dendritic arbors of these neurons. We found differences between these strains in several morphological parameters. For example, CA1 apical dendrites were more branched and complex in LEW than in F344 rats, while the spine density in the collateral dendrites of the apical dendritic arbors was greater in F344 rats. Interestingly, cocaine self-administration in LEW rats augmented the spine density, an effect that was not observed in the F344 strain. These results reveal significant structural differences in CA1 pyramidal cells between these strains and indicate that cocaine self-administration has a distinct effect on neuron morphology in the hippocampus of rats with different genetic backgrounds.
长期接触可卡因会导致参与成瘾的脑区神经元发生改变。因此，我们通过将细胞内注射路西法黄与标记神经元的共聚焦显微镜重建相结合，评估了可卡因对Fischer 344（F344）和Lewis（LEW）大鼠海马CA1区的影响，这两种品系已被广泛用于研究药物成瘾的遗传易感性。具体而言，我们研究了可卡因自我给药对CA1锥体神经元顶树突的结构、大小和分支复杂性的影响。此外，我们对这些神经元顶树突分支的侧支中的棘密度进行了量化。我们发现这两种品系在几个形态学参数上存在差异。例如，LEW大鼠的CA1顶树突比F344大鼠的分支更多且更复杂，而F344大鼠顶树突分支的侧支中的棘密度更大。有趣的是，LEW大鼠的可卡因自我给药增加了棘密度，而F3品系中未观察到这种效应。这些结果揭示了这两种品系的CA1锥体细胞在结构上存在显著差异，并表明可卡因自我给药对具有不同遗传背景的大鼠海马中的神经元形态有不同的影响。
