Remodeling of Membrane Properties and Dendritic Architecture Accompanies the Postembryonic Conversion of a Slow into a Fast Motoneuron

摘要: The postembryonic acquisition of behavior requires alterations in neuronal circuitry, which ultimately must be understood as specific changes structure, membrane properties, and synaptic connectivity. This study addresses this goal by describing the remodeling excitability dendritic morphology an identified motoneuron, MN5, during metamorphosis Manduca sexta (L.) from a slow motoneuron that is involved larval-crawling into fast adult flight motoneuron. A fivefold lower input resistance, higher firing threshold, increase voltage-activated K+current contribute to prerequisite for its newly acquired behavioral role. In addition, MN5 displays larger Ca2+ currents. dendrites undergo extensive remodeling. Drastic regression larval early pupal stages followed rapid growth new dendrites. Critical take place onset dendrite formation. Larval Ca2+currents are absent when most dramatic but markedly later development. Changes K+ currents follow different time courses, allowing transient occurrence spikes branching ceases. can produce prolonged after reduced. We suggest necessary participation production may influence