EN
The aim of the study was to investigate S100ß protein in astrocytes of CA1 and CA3 areas of the hippocampus proper and the dentate gyrus with the hilus yet undefined in mature males of chinchilla, llie presence of S100ß was determined using indirect immunohistochemical peroxidase-antiperoxidase method with specific monoclonal antibody against this protein. Most of the S100ß-positive cells were detected in the subgranular zone of the dentate gyrus and in the middle part of the hilus. In CA3 area, it was found that the most numerous cells with S100ß are in stratum radiatum. In CA1 area, there were single astrocytes expressing this protein. This data demonstrates species differences and a large quantity of S100ß immunoreactive cells in the subgranular zone of the dentate gyrus of chinchilla, which may be associated with structural reorganisation of the hippocampus and with neurogenesis, learning, and memorising process dependent on the hippocampus.