Tonic GABAAConductance Favors Spike-Timing-Dependent over Theta-Burst-Induced Long-Term Potentiation in the Hippocampus

• DOI: 10.1523/jneurosci.2118-19.2020
• Publication Date: 2020-04-23T21:45:20Z
• Authors: Yulia Dembitskaya; Yu-Wei Wu; Alexey Semyanov
• Keywords: Tonic (physiology)

Synaptic plasticity is triggered by different patterns of network activity. Here, we investigated how LTP in CA3-CA1 synapses induced stimulation affected tonic GABA A conductances rat hippocampal slices. Spike-timing-dependent was pairing Schaffer collateral with antidromic CA1 pyramidal neurons. Theta-burst-induced theta-burst collaterals. We mimicked increased conductance bath application 30 μ m GABA. Surprisingly, selectively suppressed theta-burst-induced but not spike-timing-dependent LTP. combined whole-cell patch-clamp electrophysiology, two-photon Ca 2+ imaging, glutamate uncaging, and mathematical modeling to dissect the mechanisms underlying these differential effects conductance. found that transients during an action potential EPSP were less sensitive conductance-induced shunting inhibition than burst. Our results may explain forms memory are increasing under physiological or pathologic conditions, as well influence substances target extrasynaptic receptors (e.g., neurosteroids, sedatives, antiepileptic drugs, alcohol). SIGNIFICANCE STATEMENT Brain activity associated neuronal firing synaptic signaling among represents a mechanism for learning memory. However, some neurotransmitters escape cleft released astrocytes can receptors. Extrasynaptic mediate reduce excitability neurons shunting. This decreased ability fire potentials, when potentials successfully triggered, unable them significantly. As such, have minimal on while strongly attenuating evoked bursts. findings shed light changes affect