Figure 5.

SAT1 immunostaining is enriched in hippocampal interneurons. (A) The hippocampal formation contains dispersed cells strongly immunostained for SAT1 while the principal cells are weakly immunostained. The neuropil is moderately stained in the vicinity of the principal cells (P and G) and in stratum lacunosum-moleculare (LM). (B) SAT1 immunostaining is abolished on preincubation of SAT1 antibody with the fusion protein used for immunization. (C) High power light microscopy confirms strong SAT1 immunostaining of non-pyramidal cells and their processes between faintly labeled pyramidal cells of CA1. Intracellular stained structures are visible. (D) Two SAT1 immunostained cells in the stratum oriens of CA1. Note that SAT1 immunoreactivity extends to the distal parts of their processes. (E) The dentate area also possesses scattered cells strongly stained for SAT1. Note their prominently SAT1 stained processes. (F) A SAT1 immunostained neuron with its cell body located in the basal part of the granule cell layer. Note that it extends a immunostained process vertically between unstained granule cells (g) and a horizontal process along the inner border of the granule cell layer (arrow). G, granule cell layer; g, granule cell; H, hilus; LM, stratum lacunosum-moleculare; M, stratum molecular of the area dentata; O, stratum oriens; P, stratum pyramidale; p, pyramidal cell; R, stratum radiatum. Scale bars: 20 μm (C, D, F), 75 μm (E), 150 μm (A,B).