Learning-induced enhancement of feedback inhibitory synaptic transmission.
Olfactory-discrimination learning results with a series of intrinsic and excitatory synaptic modifications in piriform cortex pyramidal neurons. Here we show that such learning results with long-lasting enhancement of inhibitory synaptic transmission onto proximal dendrites of these pyramidal neurons. Such enhancement is mediated by a strong hyperpolarizing shift in the reversal potential of fast inhibitory postsynaptic potentials (fIPSPs). Moreover, paired-pulse depression of these IPSPs, indicating enhanced GABA release, is also apparent after learning. We suggest that learning is accompanied by long-lasting enhancement of synaptic inhibition onto excitatory neurons, thus compensating for the increase of excitation in these neurons.
Brosh
Inbar
I
Departments of Neurobiology and Biology, Faculty of Sciences, University of Haifa 31905, Israel.
Barkai
Edi
E
D004193:Discrimination Learning; D005246:Feedback; D006801:Humans; D009433:Neural Inhibition / Q000502:physiology*; D012903:Smell; D009435:Synaptic Transmission / Q000502:physiology*; D005680:gamma-Aminobutyric Acid / Q000502:physiology
D005680:gamma-Aminobutyric Acid