Different Neurogenic Potential in the Subnuclei of the Postnatal Rat Cochlear Nucleus

Figure 1

The dissected CN subnuclei form neurospheres in free-floating cell cultures in NSC medium. (a) Schematic overview of the topographical arrangement of the CN subnuclei, the auditory nerve, and the cochlea (AVCN = anteroventral cochlear nucleus; PVCN = posteroventral cochlear nucleus; DCN = dorsal cochlear nucleus). The tonotopic organization of the N.VIII fibers is maintained in all subnuclei. (b) Microscopic reflected light image of a PND 9 CN preparation and labeling of the subnuclei and the cochlear nerve (N.VIII) before dissection. (c) Dissociated cells of the CN subnuclei form neurospheres in free-floating cell cultures under the influence of EGF and bFGF. The quantitative evaluation after 30 days showed that the PVCN has the significantly greatest potential for the formation of neurospheres with (; ) spheres per 1000 initially cultured single cells. (d) Evaluation of the neurosphere diameters after 4 weeks in free-floating cultures. The diameters averaged 101.2-122.6 μm. No significant differences were found between the subnuclei. Box plots show the median with the upper and lower quartiles, and whiskers mark the upper and lower maximum values; asterisks indicate the significance level: , , , and .

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