Figure 3

Expression of HCN1 in parvalbumin (PV)-positive cells of the hippocampus at P21. (A, E, I): The strongest labeling for HCN1 was observed in the sl-m and alveus of the CA. Note also that its expression was gradually stronger in the so, sp, and sr of the CA2 (E) and CA3 (I) compared to CA1 (A). (A, B, D): PV-positive cells located in the sp of the CA1 did not show HCN1 immunolabeling, whereas PV-positive cells in the so or sr of the CA1 were labeled for HCN1. In the CA2, CA3, and hilus of the DG, most PV-immunopositive cells were labeled for HCN1. A-B, D: yellow arrows indicate PV-positive/HCN1-negative cells. A-B, D-F, H-J, L-N, P: white arrows indicate PV-positive/HCN1-positive cells. C, G, K, O: DAPI staining. Scale bars = 20 μm.