Visinin-like protein (VILIP) is a neuronal EF-hand Ca(2+)-binding protein. In the chick brain, it is widely expressed, e.g. in neurons of the visual pathway and the cerebellum. In the cerebellum, a presynaptic localization of VILIP in glutamatergic parallel- and climbing-fiber terminals has been observed. Here, we describe the distribution of immunoreactivity (IR) detected by antibodies against chick VILIP in the gerbil hippocampus at the light and electron microscopic level. VILIP antibodies stain neurons in the whole hippocampal formation including pyramidal cells in the CA1 and CA3 region of the Ammon's horn and granule cells of the dentate gyrus. In CA3 neurons, VILIP-IR is localized in dendrites and dendritic spines.