Postsynaptic excitability is necessary for strengthening of cortical sensory responses during experience-dependent development.
Sensory experience is necessary for normal cortical development. This has been shown by sensory deprivation and pharmacological perturbation of the cortex. Because these manipulations affect the cortical network as a whole, the role of postsynaptic cellular properties during experience-dependent development is unclear. Here we addressed the developmental role of somatodendritic excitability, which enables postsynaptic spike timing-dependent forms of plasticity, in rat somatosensory cortex. We used short interfering RNA (siRNA)-based knockdown of Na+ channels to suppress the somatodendritic excitability of small numbers of layer 2/3 pyramidal neurons in the barrel cortex, without altering the ascending sensory pathway. In vivo recordings from siRNA-expressing cells revealed that this manipulation interfered with the normal developmental strengthening of sensory responses. The sensory responsiveness of neighboring cortical neurons was unchanged, indicating that the cortical network was unchanged. We conclude that somatodendritic excitability of the postsynaptic neuron is needed for the regulation of synaptic strength in the developing sensory cortex.
Komai
Shoji
S
Department of Biomedical Optics, Max Planck Institute for Medical Research, Jahnstrasse 29, 69120 Heidelberg, Germany.
Licznerski
Pawel
P
Cetin
Ali
A
Waters
Jack
J
Denk
Winfried
W
Brecht
Michael
M
Osten
Pavel
P
D000818:Animals; D004274:DNA, Recombinant / Q000008:administration & dosage / Q000235:genetics; D019706:Excitatory Postsynaptic Potentials / Q000502:physiology*; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D016086:Lentivirus / Q000235:genetics; D018613:Microscopy, Confocal; D009473:Neuronal Plasticity / Q000502:physiology*; D017966:Pyramidal Cells / Q000378:metabolism / Q000502:physiology; D034622:RNA Interference / Q000502:physiology; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012683:Sensory Deprivation / Q000502:physiology; D015222:Sodium Channels / Q000235:genetics / Q000502:physiology*; D013003:Somatosensory Cortex / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology
D004274:DNA, Recombinant; D034741:RNA, Small Interfering; D015222:Sodium Channels; D049452:Green Fluorescent Proteins