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The developmental profile of visual cortex astrocytes.

ABSTRACT: We investigated how astrocytes in layer 5 mouse visual cortex mature over postnatal days (P) 3-50. Across this age range, resting membrane potential increased, input resistance decreased, and membrane responses became more passive with age. Two-photon (2p) and confocal imaging of dye-loaded cells revealed that gap-junction coupling increased starting ∼P7. Morphological reconstructions revealed increased branch density but shorter branches after P20, suggesting that astrocyte branches may get pruned as tiling is established. Finally, we visualized spontaneous Ca²⁺ transients with 2p microscopy and found that Ca²⁺ events decorrelated, became more frequent and briefer with age. As astrocytes mature, spontaneous Ca²⁺ activity thus changes from relatively cell-wide, synchronous waves to local transients. Several astrocyte properties were stably mature from ∼P15, coinciding with eye opening, although morphology continued to develop. Our findings provide a descriptive foundation of astrocyte maturation, useful for the study of astrocytic impact on visual cortex critical period plasticity.

SUBMITTER: Watanabe A

PROVIDER: S-EPMC10212985 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature

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The developmental profile of visual cortex astrocytes.

Watanabe Airi A Guo Connie C Sjöström Per Jesper PJ

iScience 20230506 6

We investigated how astrocytes in layer 5 mouse visual cortex mature over postnatal days (P) 3-50. Across this age range, resting membrane potential increased, input resistance decreased, and membrane responses became more passive with age. Two-photon (2p) and confocal imaging of dye-loaded cells revealed that gap-junction coupling increased starting ∼P7. Morphological reconstructions revealed increased branch density but shorter branches after P20, suggesting that astrocyte branches may get pru ...[more]

PMID: 37250801

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Dataset Information

The developmental profile of visual cortex astrocytes.

Publications

The developmental profile of visual cortex astrocytes.

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