Ultrastructure of Teleost Retina II: Interstitial Amacrines, Dislocated Amacrines, Ganglion Cells, Müller Fiber, Oligodendroglia, Adrenergic Terminals, Inner Plexiform Layer, Glycogen Cytochemistry

Aims: To analyze the ultrastructure of internal interstitial amacrine cell, dislocated amacrine cell, ganglion cells, oligodendroglia, Müller cells, inner plexiform layer, adrenergic terminals, as well as the connections found between the cells and the cytochemistry of glycogen distribution from Mugil brasiliensis teleost retina.

Methodology: The retina was fixed with glutaraldehyde and osmium tetroxide and radial and tangential sections stained with lead citrate and uranyl acetate to be observed in a Hitachi 11B electron microscope at 75Kv. To demonstrate glycogen fragments glutaraldehyde fixed osmium post-fixed were, sectioned in the MT2 ultramicrotome and processed with periodic acid thiosemicarbizide for oxidized molecules.

Results: Retinal morphology revealed external interstitial amacrine cells as the most voluminous cell above inner plexiform layer. Dislocated amacrine cells described by the first time, localized at the inner plexiform layer, had clear cytoplasm, few ribosomes, few vesicles of rough endoplasmic reticulum and elongated mitochondria with clear matrix. Dark and clear amacrine piriform cells were characterized by glycogen density, and their functional contacts described. External horizontal cells, dark piriform amacrines, stellate amacrines and Müller cells exhibited the highest glycogen concentration in teleost fish retina.

Conclusion: This paper is a comprehensive analysis of ultrastructure of five retinal cells, adrenergic terminals inner plexiform layer and glycogen distribution in the retina, finding one new cell, the dislocated amacrine cell and also describing the amacrine interstitial external cell the most voluminous cell in teleost retina.