Networks of coactive neurons in developing layer 1.
Spontaneous neuronal activity plays an important role in the development of cortical circuitry, yet its spatio-temporal dynamics are poorly understood. Cajal-Retzius (CR) neurons in developing layer 1 are necessary for correct cortical lamination and are strategically located to coordinate early circuit activity. To characterize the spontaneous activity of CR and other layer 1 neurons during cortical development, we imaged calcium transients in populations of layer 1 neurons in hemispheres and slices from postnatal rat somato-sensory neocortex. The spontaneous activity in layer 1 had complex spatio-temporal patterns. Groups of non-CR cells showed synchronous activations and formed networks of correlated neurons superimposed in the same territory. Correlated activity among non-CR cells was mediated by a depolarizing effect of GABA and was modulated by glutamate, probably released by CR cells. Our findings demonstrate that developing layer 1 can sustain complex patterns of correlated activity and reveal a circuit mechanism that can mediate this patterned activity.
Schwartz
T H
TH
Department of Biological Sciences, Columbia University, New York, New York 10027, USA.
Rabinowitz
D
D
Unni
V
V
Kumar
V S
VS
Smetters
D K
DK
Tsiola
A
A
Yuste
R
R
D000109:Acetylcholine / Q000494:pharmacology; D000316:Adrenergic alpha-Agonists / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002540:Cerebral Cortex / Q000166:cytology* / Q000254:growth & development*; D004558:Electric Stimulation; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D018755:GABA Agonists / Q000494:pharmacology; D018698:Glutamic Acid / Q000494:pharmacology; D009118:Muscimol / Q000494:pharmacology; D016202:N-Methylaspartate / Q000494:pharmacology; D009474:Neurons / Q000737:chemistry / Q000502:physiology*; D018377:Neurotransmitter Agents / Q000378:metabolism; D009638:Norepinephrine / Q000494:pharmacology; D009924:Organ Culture Techniques; D018408:Patch-Clamp Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D013779:Tetrodotoxin / Q000494:pharmacology; D013997:Time Factors; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000494:pharmacology; D005680:gamma-Aminobutyric Acid / Q000502:physiology
D000316:Adrenergic alpha-Agonists; D018690:Excitatory Amino Acid Agonists; D018755:GABA Agonists; D018377:Neurotransmitter Agents; D009118:Muscimol; D018698:Glutamic Acid; D013779:Tetrodotoxin; D005680:gamma-Aminobutyric Acid; D016202:N-Methylaspartate; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D000109:Acetylcholine; D002118:Calcium; D009638:Norepinephrine