# CA1 Oriens Lacunosum Moleculare: Saraga *et al*, 2003

## Summary

It is well known that interneurons are heterogeneous in their morphologies, biophysical properties, pharmacological sensitivities and electrophysiological responses, but it is unknown how best to understand this diversity. Given their critical roles in shaping brain output, it is important to try to understand the functionality of their computational characteristics. To do this, we focus on specific interneuron subtypes. In particular, it has recently been shown that long-term potentiation is induced specifically on oriens-lacunosum/moleculare (O-LM) interneurons in hippocampus CA1 and that the same cells contain the highest density of dendritic sodium and potassium conductances measured to date. We create multi-compartment models of an O-LM hippocampal interneuron using passive properties, channel kinetics, densities and distributions specific to this cell type, and explore its signaling characteristics. We find that spike initiation depends on both location and amount of input, as well as the intrinsic properties of the interneuron. Distal synaptic input always produces strong back-propagating spikes whereas proximal input could produce both forward and back-propagating spikes depending on the input strength. We speculate that the highly active dendrites of these interneurons endow them with a specialized function within the hippocampal circuitry by allowing them to regulate direct and indirect signaling pathways within the hippocampus.

## Versions of the project

### NEURON Simulation

This model can run by starting the mosinit.hoc with:

`nrngui mosinit.hoc`

or double clicking on the mosinit.hoc file after the mod files have been compiled (nrnivmodl compiles in unix, mknrndll in mswin, mac)

Select a figure by clicking on a figure name.

## Previously Reported Bugs

20150416 Note from the ModelDB administrator: A bug noted by Mohamed

Sherif and fix provided by Ted Carnevale updates the IA.mod file so

that the a,b states change.