Presynaptic miniature GABAergic currents in developing interneurons.
Miniature synaptic currents have long been known to represent random transmitter release under resting conditions, but much remains to be learned about their nature and function in central synapses. In this work, we describe a new class of miniature currents ("preminis") that arise by the autocrine activation of axonal receptors following random vesicular release. Preminis are prominent in gabaergic synapses made by cerebellar interneurons during the development of the molecular layer. Unlike ordinary miniature postsynaptic currents in the same cells, premini frequencies are strongly enhanced by subthreshold depolarization, suggesting that the membrane depolarization they produce belongs to a feedback loop regulating neurotransmitter release. Thus, preminis could guide the formation of the interneuron network by enhancing neurotransmitter release at recently formed synaptic contacts.
Trigo
Federico F
FF
CNRS, Unité 8118, Université Paris Descartes, 75006 Paris, France.
Bouhours
Brice
B
Rostaing
Philippe
P
Papageorgiou
George
G
Corrie
John E T
JE
Triller
Antoine
A
Ogden
David
D
Marty
Alain
A
D000818:Animals; D002531:Cerebellum / Q000378:metabolism / Q000502:physiology; D004594:Electrophysiology; D053444:Inhibitory Postsynaptic Potentials / Q000502:physiology; D007395:Interneurons / Q000378:metabolism / Q000502:physiology*; D008854:Microscopy, Electron; D055369:Miniature Postsynaptic Potentials / Q000502:physiology; D009433:Neural Inhibition / Q000502:physiology*; D017729:Presynaptic Terminals / Q000378:metabolism / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013569:Synapses / Q000378:metabolism / Q000502:physiology; D009435:Synaptic Transmission / Q000502:physiology*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
D005680:gamma-Aminobutyric Acid