Expression of dendrin, neurofilament and glial fibrillary acidic protein in the brain of the dogfish Scyliorhinus canicula L.

Background and purpose: Dendrin is a brain and renal protein that is supposed to be involved in cytoskeletal modifications at the synapse and a part of the slit diaphragm and podocytes. Here, we aimed to investigate dendrin expression in dogfish brain since this newly discovered protein was never reported in fish. We compared the expression of dendrin to those of glial (GFAP) and neuronal (NF) proteins, which have already been described in the dogfish brain. Materials and methods: Histological and immunofluorescent techniques were performed on tissue samples. The obtained data were statistically analyzed. Results: Our results have shown that dendrin is expressed in all observed parts of the dogfish brain. In the forebrain, both observed parts (telencephalon and olfactory lobes) expressed dendrin. Regarding the percentage area of dendrin expression, it is expressed more in olfactory lobes than in the telencephalon. Compared with GFAP and NF expression, the expression of dendrin significantly differs in both parts of the forebrain. The highest dendrin expression was noticed in the midbrain. In dogfish midbrain, the difference in expression of dendrin in comparison to those of GFAP and NF was even more significant. The percentage area of dendrin expression in the hindbrain (cerebellum and medulla oblongata) was smaller than those in the forebrain and midbrain, contrary the percentage area of intermediate filaments GFAP and NF were significantly higher. Conclusion: These results are the first report on dendrin expression in the dogfish brain opening the path for future studies on its role and function.