The spike-timing-dependent plasticity of VIP interneurons in motor cortex.
Front Cell Neurosci
; 18: 1389094, 2024.
Article
de En
| MEDLINE
| ID: mdl-38706517
ABSTRACT
The plasticity of inhibitory interneurons (INs) plays an important role in the organization and maintenance of cortical microcircuits. Given the many different IN types, there is an even greater diversity in synapse-type-specific plasticity learning rules at excitatory to excitatory (EâI), IâE, and IâI synapses. IâI synapses play a key disinhibitory role in cortical circuits. Because they typically target other INs, vasoactive intestinal peptide (VIP) INs are often featured in IâIâE disinhibition, which upregulates activity in nearby excitatory neurons. VIP IN dysregulation may thus lead to neuropathologies such as epilepsy. In spite of the important activity regulatory role of VIP INs, their long-term plasticity has not been described. Therefore, we characterized the phenomenology of spike-timing-dependent plasticity (STDP) at inputs and outputs of genetically defined VIP INs. Using a combination of whole-cell recording, 2-photon microscopy, and optogenetics, we explored IâI STDP at layer 2/3 (L2/3) VIP IN outputs onto L5 Martinotti cells (MCs) and basket cells (BCs). We found that VIP INâMC synapses underwent causal long-term depression (LTD) that was presynaptically expressed. VIP INâBC connections, however, did not undergo any detectable plasticity. Conversely, using extracellular stimulation, we explored EâI STDP at inputs to VIP INs which revealed long-term potentiation (LTP) for both causal and acausal timings. Taken together, our results demonstrate that VIP INs possess synapse-type-specific learning rules at their inputs and outputs. This suggests the possibility of harnessing VIP IN long-term plasticity to control activity-related neuropathologies such as epilepsy.
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Langue:
En
Journal:
Front Cell Neurosci
Année:
2024
Type de document:
Article
Pays d'affiliation:
Canada
Pays de publication:
Suisse