Summary of molecular, electrophysiological, and morphological properties of L1 interneurons
| Cell type | Molecular profile | Electrophysiological properties | Morphological properties |
|---|---|---|---|
| Neurogliaform cells (NGFCs) | NDNF+NPY+ | Late spiking (LS): non-adapting spike trains | Dense elongated axonal arbor confined to L1 |
| Canopy cells | NDNF+NPY- | Non-LS: onset spike(s) at the start of threshold depolarizations; spike trains with moderate spike frequency adaptation; lack near threshold active depolarizing hump as in α7 cells | Elongated axonal arbor largely confined to the upper half of L1; axonal arbor less dense than in NGFCs |
| α7 cells | NDNF- α7 nAChR+ | Non-LS: onset spike(s) at the start of threshold depolarizations; spike trains with moderate spike frequency adaptation; prominent near threshold active depolarizing hump; large Ih-mediated hyperpolarizing sag | Somas in lower half of L1; axon collaterals descending to L5A; largest soma size of all L1 cells; multipolar dendrite |
| VIP cells | NDNF- VIP+ | Non-LS: fast-adapting; onset spike(s) at the start of threshold depolarizations; spike trains with strong spike frequency adaptation; high input resistance | Somas in lower half of L1; axon collaterals descending to L6, branching in L5A; smallest soma size of all L1 cells; bipolar dendrite |