Quantitative histochemistry of timm-staining in the right and left rat hippocampus: Lack of right-left asymmetries

Abstract

Biochemical and behavioral studies demonstrated lateralized differences in several areas of the rat limbic system. However, no significant right-left differences in several morphological parameters of the hippocampus were reported in some anatomical studies. To evaluate further possible asymmetries in microanatomy of the rat hippocampus the intensity of Timm-staining in different hippocampal fields and the area occupied by mossy fibres were assessed using combined microdensitometric and quantitative image analysis techniques. Timm-staining is a sensitive marker for the histochemical detection of zinc and other heavy transition metals and it is considered to be related to the distribution of intrahippocampal association pathways. No right-left differences were seen in the density of Timm-staining at the level of the dentate gyrus and in the dendritic layer of CA1 and Ca2 fields, in the mossy fibre area or in the subiculum. These findings support the view of lack of morphologic asymmetry in the rat hippocampus. © 1990, JAPAN SOCIETY OF HISTOCHEMISTRY AND CYTOCHEMISTRY. All rights reserved.