Figure 2.
Morphological features of pyramidal cells recorded and filled in the CA1 and CA2 regions of the adult rat hippocampus. A, B, Neurolucida reconstructions of CA2 pyramidal cells. Like those in CA1, the dendritic arbors of CA2 pyramidal cells (black) extended through SO and SLM. Their axons (gray) arborized either exclusively in SO (A) or in SO and SR of the CA2 and CA3 regions (B). C, Neurolucida reconstruction of a typical CA1 pyramidal cell. The dendritic arbor (black) extended through all layers, and the axon (gray) emitted collaterals in SO. D, Number of dendritic branches against the distance from the soma of CA1 and CA2 pyramidal cells. All data are represented as mean ± SD. E, Length of apical and basal dendrites of CA1 and CA2 pyramidal cells. CA2 pyramidal cells had longer basal and shorter apical dendrites than CA1 pyramidal cells (Mann–Whitney U test, p < 0.05; Ubasal = 3, Uapical = 0; nCA1 = 6, nCA2 = 6).