RESUMEN
Aim To investigate the distribution of postsynaptic density protein 95 (PSD95) and AMPA receptor GluA2 subunit during the maturation of rat hippocampal neurons in vitro. Methods Cultured rat hippocampal neurons at 4(days in vitro, DIV), 7DIV, 14DIV and 20DIV were used in an immunofluorescence assay to test co-localization of PSD95 and GluA2 by laser confocal microscope at a magnification of 60 ×. Results PSD95 puncta were gradually distributed densely in dendrites and dendritic spines during neuron maturation progresses. GluA2 subunits were uniformly distributed in the cell body, axons, dendrites and dendritic spines. The Pearson' s correlation of PSD95 and GluA2 was 0. 830 ±0. 033 and 0. 734 ±0. 019 respectively at the dendrites of 4DIV and 7DIV neurons, which showed strong co-localization. While at the dendrites of 14DIV and 20DIV neurons, a moderate correlation was demonstrated by the Pearson correlation 0. 547 ± 0. 021 and 0. 574 ± 0. 024. Conclusions GluA2 has no specific intracellular distribution during neuron maturation, while the functional localization of PSD95 depends on the appearance of dendritic spines. The co-localization of GluA2 with PSD95 in dendritic spines suggests that there are stable synapses containing AMPA receptors.