Bidirectional control of spike timing by GABA(A) receptor-mediated inhibition during theta oscillation in CA1 pyramidal neurons.
Precisely controlled spike times relative to theta-frequency network oscillations play an important role in hippocampal memory processing. Here we study how inhibitory synaptic input during theta oscillation contributes to the control of spike timing. Using whole-cell patch-clamp recordings from CA1 pyramidal cells in vitro with dynamic clamp to simulate theta-frequency oscillation (5 Hz), we show that gamma-aminobutyric acid-A (GABA(A)) receptor-mediated inhibitory postsynaptic potentials (IPSPs) can not only delay but also advance the postsynaptic spike depending on the timing of the inhibition relative to the oscillation. Spike time advancement with IPSP was abolished by the h-channel blocker ZD7288 (10 microM), suggesting that IPSPs can interact with intrinsic membrane conductances to yield bidirectional control of spike timing.
Kwag
Jeehyun
J
Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK. jeehyun.kwag@dpag.ox.ac.uk
Paulsen
Ole
O
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D004558:Electric Stimulation; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D066298:In Vitro Techniques; D053444:Inhibitory Postsynaptic Potentials / Q000502:physiology; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D049990:Membrane Transport Modulators / Q000494:pharmacology; D009433:Neural Inhibition / Q000502:physiology*; D018408:Patch-Clamp Techniques; D017966:Pyramidal Cells / Q000187:drug effects / Q000502:physiology*; D011743:Pyrimidines / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D011963:Receptors, GABA-A / Q000378:metabolism*; D013826:Theta Rhythm; D013997:Time Factors
D049990:Membrane Transport Modulators; D011743:Pyrimidines; D011963:Receptors, GABA-A; C082246:ICI D2788