Hippocampus is divided into distinct regions in vivo: CA1 and CA3 of Ammon’s horn, and the dentate gyrus (DG) . CA fields and DG consist of neurons with large pyramidal somata and small granule somata, respectively. Besides the cell morphology, it is known that DG granule neurons express Prox1 (prospero-related homeobox 1), while CA3 pyramidal neurons express KA1 (kainate acid 1, also known as grik4: glutamate receptor ionotropic kainate 4
All the sections picture here are cornal sections. Hippocampus is located on the most medial part of temporal lobe (lateral structure)
Gw13 human fetal hippocampus coronal section
