Cell-specific, spike timing-dependent plasticities in the dorsal cochlear nucleus.
In the dorsal cochlear nucleus, long-term synaptic plasticity can be induced at the parallel fiber inputs that synapse onto both fusiform principal neurons and cartwheel feedforward inhibitory interneurons. Here we report that in mouse fusiform cells, spikes evoked 5 ms after parallel-fiber excitatory postsynaptic potentials (EPSPs) led to long-term potentiation (LTP), whereas spikes evoked 5 ms before EPSPs led to long-term depression (LTD) of the synapse. The EPSP-spike protocol led to LTD in cartwheel cells, but no synaptic changes resulted from the reverse sequence (spike-EPSP). Plasticity in fusiform and cartwheel cells therefore followed Hebbian and anti-Hebbian learning rules, respectively. Similarly, spikes generated by summing EPSPs from different groups of parallel fibers produced LTP in fusiform cells, and LTD in cartwheel cells. LTD could also be induced in glutamatergic inputs of cartwheel cells by pairing parallel-fiber EPSPs with depolarizing glycinergic PSPs from neighboring cartwheel cells. Thus, synaptic learning rules vary with the postsynaptic cell, and may require the interaction of different transmitter systems.
Tzounopoulos
Thanos
T
Oregon Hearing Research Center and Vollum Institute, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, Oregon 97239, USA. tzounopo@ohsu.edu
Kim
Yuil
Y
Oertel
Donata
D
Trussell
Laurence O
LO
D000818:Animals; D000831:Animals, Newborn; D017626:Cochlear Nucleus / Q000166:cytology / Q000502:physiology*; D004307:Dose-Response Relationship, Radiation; D004558:Electric Stimulation / Q000379:methods; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology; D005998:Glycine / Q000494:pharmacology; D018684:Glycine Agents / Q000494:pharmacology; D066298:In Vitro Techniques; D017774:Long-Term Potentiation / Q000187:drug effects / Q000502:physiology; D051379:Mice; D008813:Mice, Inbred ICR; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology; D009473:Neuronal Plasticity / Q000502:physiology*; D009474:Neurons / Q000145:classification / Q000502:physiology*; D018408:Patch-Clamp Techniques / Q000379:methods; D011810:Quinoxalines / Q000494:pharmacology; D013331:Strychnine / Q000494:pharmacology; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D013997:Time Factors; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000494:pharmacology
D018690:Excitatory Amino Acid Agonists; D018691:Excitatory Amino Acid Antagonists; D018684:Glycine Agents; D011810:Quinoxalines; C056723:FG 9041; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D013331:Strychnine; D005998:Glycine