Abstract
The purpose of the present study was to test the possibility of identifying hippocampal mossy fiber projections by staining mouse brain sections with antibodies to the claudin-2 protein.
Material and methods: the subjects of the study were 9 male wild mice. Serial frontal sections of the brain were prepared using a cryostat. In order to identify hippocampal mossy fiber projections, sections were immunohistochemically stained with polyclonal antibodies to the claudin-2 protein and analyzed under a fluorescence microscope. The resulting images were processed in ZEN and ImageJ software, then the morphometric parameters were compared with literature data on staining of mossy fibers with antibodies to the zinc transporter ZNT3.
Results: Our results suggest that claudin-2 can be used as a marker of hippocampal mossy fibers in mice. The staining pattern obtained with antibodies to claudin-2 replicates that obtained with Timm staining of mossy fibers or with antibodies to the zinc transporter ZNT3: intense staining of the hilus of the dentate gyrus, with a clear pattern of infra- and suprapyramidal mossy fibers, including in the area of the stratum lucidum. The total area of dorsal hippocampal mossy fibers identified by claudin-2 antibodies was not statistically significantly different from the area measured by ZNT3 staining.
Conclusion: Immunohistochemical staining of mouse brain sections for claudin-2 can be used to identify hippocampal mossy fibers.
Authors and affiliations
A. Ismailova, K.V. Ichetkina, E.A. Kurilova, O.P. Tuchina
Immanuel Kant Baltic Federal University, Educational and scientific cluster “Institute of Medicine and Life Sciences (MEDBIO)”,
High School of life sciences, Laboratory for Synthetic biology, ul. Universitetskaya, 2, Kaliningrad, 236041, Russian Federation
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