Cochlear organotypic cultures and histological examinations in rats

OBJECTIVE Exploration of project is to introduce a cochlear organotypic culture technique and the histological evaluation of cochlear hair cells, auditory nerve fibers, and spiral ganglion neurons from rat on post-natal day 3. METHODS The cochlear basilar membrane was placed on the surface of rattail collagen gel in culture medium. The cochlear specimens were double-labeled with FITC-conjugated phalloidin for showing the stereocilia and cuticular plate of the hair cells plus a monoclonal antibody against neurofilament 200 for showing the spiral ganglion neurons and their auditory nerve fibers. Specimens were observed under a Confocal Laser Scanning Microscope with appropriate filters. RESULTS Following the culturing period of 1 to 3 days, cochlear inner and outer hair cells presented normal without any contabescence or missing. The auditory nerve fibers were in an orderly arrangement and the morphology of spiral ganglion neurons were also in good shape. CONCLUSION The cochlear organotypic culture technique and the histological examinations will be helpful to evaluate the cochlear hair cells and the spiral ganglion neurons in various experimental models in vitro.