Histochemical characterization of the olfactory epithelium of an Indian major carp, Catla catla (Hamilton, 1822)

The present study is related to the histochemical investigations on the changes in the intensity of reactions of axons, acid and neutral mucopolysaccharides, biologically active macromolecules, particularly glycogen and protein component as well as alkaline phosphatase (ALPase) and adenosine triphosphatase (ATPase) in the cells lining the olfactory epithelium of Catla catla. The intense reaction of silver stain was well-marked in the primary receptor cells and in the synaptic contacts between primary and secondary receptor cells. The maximum intensity of reaction of acid and neutral mucin as well as protein, was discernible in the secretory and non-secretory mucous cells. Various shades of glycogen were detected in the receptor cells, stratified epithelial cells and mucous cells. Concentration of ALPase was found to be associated with central core along with basement membrane. Acute ATPase activity was evidenced in the receptor cells, stratified epithelial cells and basal cells of olfactory epithelium and nerve fibers in the central core. Histochemical reactions in the various cells on the olfactory epithelium were discussed with the functional importance of the fish concerned.