Slide 17

Dual Intracellular Recordings from a Synaptically Connected Perigeniculate and Thalamocortical Cells in the LGNd

Through the performance of dual intracellular recordings, we have found that the generation of a burst of action potentials in a single PGN neuron can generate an inhibitory postsynaptic potential in thalamocortical cells that is large enough to result in the occurrence of a rebound low threshold Ca2+ spike and a burst of action potentials. Interestingly, depolarization of the perigeniculate neuron not only changes this cell to the tonic firing mode, but also dramatically changes the amplitude-time course of the resulting IPSPs in the thalamocortical cell. Trains of action potentials in the PGN neuron generate only small amplitude IPSPs in thalamocortical cells. 

Recordings are by Uhnoh Kim and Thierry Bal. 

Bal and McCormick (1996) What stops thalamocortical oscillations? Neuron 17:297-308. 

Kim, U., Sanchez-Vives, M.V., and McCormick, D.A. (1997) Functional dynamics of GABAergic inhibition in the thalamus Science 278: 130-134.