Wayne E. Crill

Most neurons talk to each other by releasing neurotransmitters at thousands of synapses. The receiving cells change these chemical signals into electrical spike discharges for opening or closing molecular channels with different ion selectivities. Neurobiologists and biophysicists are rapidly identifying the structure and function of these channels, yet we only have a meager grasp of how a neuron uses these different channel types to generate signals transmitted as patterns of action potentials. Because many of these channels are modulated by neurotransmitters, the synaptic transduction properties could change from moment to moment. Our research group approaches these issues by asking questions about the role of individual ion species to this transduction process. Recently we have been interested in the functional significance of the spatial distribution in neurons of different ion channel types.

In collaboration with Peter Schwindt we use brain slices, acutely isolated brain cells, intracellular recording, patch recording and sodium and calcium imaging to answer these questions. Currently, we have a special interest in the role of voltage-dependent channels in dendrites. We are particularly interested in the voltage-dependent channels activated in the subthreshold voltage range because these channels can markedly affect the integration of dendritic synaptic input. We have recently provided evidence for several different channel types in the dendrites and have studied their role in the transmission tothe neuron spike generating region in the soma. If these dendritic channels are modulated by neurotransmitters the nervous system has a mechanism for controlling synaptic effectiveness without directly modifying synaptic transmission.