AXONAL REGENERATION OF IDENTIFIED SEPTOHIPPOCAMPAL PROJECTION NEURONSIN-VITRO

Previous studies have shown that the septohippocampal projection devel ops in vitro. It remained unclear, however, whether this in vitro proj ection resulted from axonal regeneration of septal neurons transected by the culture preparation, or from a priori outgrowth of undamaged ce lls that had not yet sent an axonal process to the hippocampus at the time of tissue preparation, Here we have prepared slice cultures of id entified septohippocampal projection neurons that were retrogradely la beled by hippocampal tracer injection prior to slice preparation. We d emonstrate that these identified projection neurons survive axotomy ca used by culture preparation, are able to regrow an axonal process in v itro, and innervate a co-cultured hippocampal slice.