Calbindin D-28K immunoreactivity in the nucleus pretectalis superficialis magnocellularis of the rainbow trout (Salmo gairdneri, teleost).

Abstract

The distribution of calbindin D-28K (CaBP28K) fibers and cell bodies in the nucleus pretectalis superficialis magnocellularis of the Salmo gairdneri was studied using a monoclonal antibody and the avidin-biotin-peroxidase method. In this nucleus a high density of long, non-branching and in general thin CaBP28K-positive fibers was found. In addition, a high density of cell bodies CaBP28K-positive was also observed in the nucleus pretectalis superficialis magnocellularis. The neurons were large and small showing a fusiform, pyriform or triangular form with one, two or more thick and long dendritic trunks branching dichotomously. In the neurons CaBP28K-immunoreactive axonic processes were also observed. It was postulated that the large perikarya could be projecting neurons whereas small cell bodies could be interneurons.