Calretinin immunoreactive neurons in the basolateral amygdala of the rat and monkey

The calcium-binding protein calretinin was localized in the basolateral amygdala (BLA) of the rat and monkey using immunohistochemical techniques. In both species the predominant cell type exhibiting calretinin-like immunoreactivity (CR-ir) was a small non-pyramidal neuron with a bipolar or bitufted dendritic arborization pattern. Some pyramidal neurons also exhibited light CR-ir. In the monkey there was an additional population of large moderately-stained neurons with well-stained dendrites. These results indicate that calretinin is found in specific cell types in BLA. The small non-pyramidal CR-ir neurons are morphologically similar to BLA neurons that exhibit immunoreactivity for vasoactive intestinal polypeptide (VIP). These CR-ir neurons in BLA closely resemble the small bipolar CR-ir neurons of the cerebral cortex.