Networks of coactive neurons in developing layer 1

Neuron. 1998 Mar;20(3):541-52. doi: 10.1016/s0896-6273(00)80993-9.

Abstract

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.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylcholine / pharmacology
  • Adrenergic alpha-Agonists / pharmacology
  • Animals
  • Calcium / metabolism
  • Cerebral Cortex / cytology*
  • Cerebral Cortex / growth & development*
  • Electric Stimulation
  • Excitatory Amino Acid Agonists / pharmacology
  • GABA Agonists / pharmacology
  • Glutamic Acid / pharmacology
  • Muscimol / pharmacology
  • N-Methylaspartate / pharmacology
  • Neurons / chemistry
  • Neurons / physiology*
  • Neurotransmitter Agents / metabolism
  • Norepinephrine / pharmacology
  • Organ Culture Techniques
  • Patch-Clamp Techniques
  • Rats
  • Rats, Sprague-Dawley
  • Synaptic Transmission / drug effects
  • Synaptic Transmission / physiology
  • Tetrodotoxin / pharmacology
  • Time Factors
  • alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / pharmacology
  • gamma-Aminobutyric Acid / physiology

Substances

  • Adrenergic alpha-Agonists
  • Excitatory Amino Acid Agonists
  • GABA Agonists
  • Neurotransmitter Agents
  • Muscimol
  • Glutamic Acid
  • Tetrodotoxin
  • gamma-Aminobutyric Acid
  • N-Methylaspartate
  • alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid
  • Acetylcholine
  • Calcium
  • Norepinephrine