19-P005 Size regulation of dorsal root ganglia in developing axolotls with an under- or oversupply of neural crest material

to correspond to the plasticity of the brain. In zebrafish many distinct constitutive proliferation zones have been described along the whole anterior–posterior axis of the brain [Grandel et al. Dev. Biol. 295 (2006) 263–277]. The cns of teleosts has an enormous capacity to regenerate after brain incisions or removal of whole brain parts, as well as after transection of the spinal cord. Neural regeneration has been demonstrated in several teleost species suggesting that it is a common feature of teleost fishes in general [Kaslin et al. Philos. Trans. R Soc. Lond. B Biol. Sci. 363 (2008) 101–122]. To investigate regenerative processes in the cns of adult zebrafish we have established a stab-wound lesion paradigm in the telencephalon. The temporal course of regenerative events was analyzed. After lesion a marked increase in proliferation was detected in the constitutive proliferation zones, as well as ectopic proliferation proximal to the lesion. We are currently analyzing the identity and proliferative properties of cells contributing to regeneration using BrdU to specifically label cycling cells combined with immunohistological detection of neuronal and glial marker proteins.