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Updated: Jun 27, 2026
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Double In Utero Electroporation to Target Temporally and Spatially Separated Cell Populations
Published on: June 14, 2020
Sequential generation of two distinct synapse-driven network patterns in developing neocortex
Camille Allène1, Adriano Cattani, James B Ackman
1Institut de Neurobiologie de la Méditerranée, Inserm U901, Université de la Méditerranée, 13273 Marseille cedex 9, France.
Summary
Developing brain networks exhibit distinct activity patterns: early network oscillations (ENOs) driven by glutamate, followed by giant depolarizing potentials (GDPs) driven by GABA. These patterns differ in timing, dynamics, and underlying mechanisms during neocortical maturation.
Area of Science:
- Neuroscience
- Developmental Biology
- Computational Neuroscience
Background:
- Developing cortical networks exhibit diverse activity patterns crucial for circuit refinement.
- Early network oscillations (ENOs) are prominent in neonatal rodent neocortex, largely driven by glutamate.
- GABA, though excitatory early on, mediates giant depolarizing potentials (GDPs) in the hippocampus.
Purpose of the Study:
- To investigate and differentiate the network dynamics of early network oscillations (ENOs) and giant depolarizing potentials (GDPs) in the developing rat somatosensory cortex.
- To elucidate the distinct developmental profiles, dynamics, and underlying mechanisms of these two network patterns.
Main Methods:
- Functional multineuron calcium imaging.
- Single-cell recordings.
- Field potential recordings in rat cortical slices.
Main Results:
- The developing somatosensory cortex first generates ENOs, followed by GDPs, with a period of coexistence.
- ENOs, occurring before GDPs, are low-frequency (0.01 Hz), slow, and involve the entire network, driven by NMDAR activation.
- GDPs, appearing later, are recurrent (0.1 Hz), synchronize localized assemblies, and are GABA-driven.
- ENOs are facilitated by anoxia and affected by extracellular glutamate levels, suggesting glutamate accumulation's role.
- A tonic glutamate current contributes to excitability during ENOs.
Conclusions:
- Cortical ENOs and GDPs are distinct network patterns with different developmental trajectories and mechanisms.
- These patterns represent separate facets of neocortical network maturation.
- Differential engagement in physiological and pathological processes is suggested for ENOs and GDPs.
