Cell type-specific long-term plasticity at glutamatergic synapses onto hippocampal interneurons expressing either parvalbumin or CB1 cannabinoid receptor.
Different GABAergic interneuron types have specific roles in hippocampal function, and anatomical as well as physiological features vary greatly between interneuron classes. Long-term plasticity of interneurons has mostly been studied in unidentified GABAergic cells and is known to be very heterogeneous. Here we tested whether cell type-specific plasticity properties in distinct GABAergic interneuron types might underlie this heterogeneity. We show that long-term potentiation (LTP) and depression (LTD), two common forms of synaptic plasticity, are expressed in a highly cell type-specific manner at glutamatergic synapses onto hippocampal GABAergic neurons. Both LTP and LTD are generated in interneurons expressing parvalbumin (PV+), whereas interneurons with similar axon distributions but expressing cannabinoid receptor-1 show no lasting plasticity in response to the same protocol. In addition, LTP or LTD occurs in PV+ interneurons with different efferent target domains. Perisomatic-targeting PV+ basket and axo-axonic interneurons express LTP, whereas glutamatergic synapses onto PV+ bistratified cells display LTD. Both LTP and LTD are pathway specific, independent of NMDA receptors, and occur at synapses with calcium-permeable (CP) AMPA receptors. Plasticity in interneurons with CP-AMPA receptors strongly modulates disynaptic GABAergic transmission onto CA1 pyramidal cells. We propose that long-term plasticity adjusts the synaptic strength between pyramidal cells and interneurons in a cell type-specific manner and, in the defined CA1 interneurons, shifts the spatial pattern of inhibitory weight from pyramidal cell dendrites to the perisomatic region.
Nissen
Wiebke
W
Department of Pharmacology, Oxford University, Oxford OX1 3QT, United Kingdom.
Szabo
Andras
A
Somogyi
Jozsef
J
Somogyi
Peter
P
Lamsa
Karri P
KP
D000818:Animals; D020013:Calcium Signaling / Q000187:drug effects / Q000502:physiology; D016764:Cell Polarity / Q000187:drug effects / Q000502:physiology; D048430:Cell Shape / Q000502:physiology; D003712:Dendrites / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D018698:Glutamic Acid / Q000378:metabolism*; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D007150:Immunohistochemistry; D007395:Interneurons / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D017774:Long-Term Potentiation / Q000187:drug effects / Q000502:physiology; D036881:Long-Term Synaptic Depression / Q000187:drug effects / Q000502:physiology; D008297:Male; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology*; D009924:Organ Culture Techniques; D010320:Parvalbumins / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D017729:Presynaptic Terminals / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D051381:Rats; D017207:Rats, Sprague-Dawley; D043884:Receptor, Cannabinoid, CB1 / Q000187:drug effects / Q000378:metabolism*; D018091:Receptors, AMPA / Q000187:drug effects / Q000378:metabolism; D013569:Synapses / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D010320:Parvalbumins; D043884:Receptor, Cannabinoid, CB1; D018091:Receptors, AMPA; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid