0000000000653539
AUTHOR
Rolf Kötter
Optical release of caged glutamate for stimulation of neurons in the in vitro slice preparation
Optical stimulation techniques prove useful to map func- tional inputs in the in vitro brain slice preparation: Glutamate released by a focused beam of UV light induces action potentials, which can be detected in postsynaptic neurons. The direct activation effect is influenced by factors such as compound concentration, focus depth, light absorption in the tissue, and sensitivity of different neuronal do- mains. We analyze information derived from direct stimulation ex- periments in slices from rat barrel cortex and construct a computa- tional model of a layer V pyramidal neuron that reproduces the experimental findings. The model predictions concerning the influ- ence of focus depth on inpu…
CoCoDat: a database system for organizing and selecting quantitative data on single neurons and neuronal microcircuitry.
We present a novel database system for organizing and selecting quantitative experimental data on single neurons and neuronal microcircuitry that has proven useful for reference-keeping, experimental planning and computational modelling. Building on our previous experience with large neuroscientific databases, the system takes into account the diversity and method-dependence of single cell and microcircuitry data and provides tools for entering and retrieving published data without a priori interpretation or summarizing. Data representation is based on the framework suggested by biophysical theory and enables flexible combinations of data on membrane conductances, ionic and synaptic current…
Guiding the modeller: organizing and selecting experimental data for single cell models using the CoCoDat database
Collating, organizing and selecting quantitative experimental data are time-consuming tasks necessary for building and constraining biophysically realistic neuronal models. The CoCoDat (Collation of Cortical Data) database has been designed as an advanced environment for storing, organizing and retrieving detailed, uninterpreted quantitative data on morphology, electrophysiology and connectivity from the published literature according to neurophysiological concepts. All experimental data are linked to exact bibliographical references and detailed records of procedures used in the experiments that produced the data. We demonstrate the usefulness of CoCoDat for implementation of an example mo…
Cell type-specific circuits of cortical layer IV spiny neurons
Sensory signal processing in cortical layer IV involves two major morphological classes of excitatory neurons: spiny stellate and pyramidal cells. It is essentially unknown how these two cell types are integrated into intracortical networks and whether they play different roles in cortical signal processing. We mapped their cell-specific intracortical afferents in rat somatosensory cortex through a combination of whole-cell patch-clamp recordings and caged glutamate photolysis. Spiny stellate cells received monosynaptic excitation and inhibition originating almost exclusively from neurons located within the same barrel. Pyramidal cells, by contrast, displayed additional excitatory inputs fr…