Activity-dependent K+ accumulation in the developing rat optic nerve.

B W Connors; B R Ransom; D M Kunis; M J Gutnick

doi:10.1126/science.7079771

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PubMed · 7079771

Activity-dependent K+ accumulation in the developing rat optic nerve.

B W Connors·B R Ransom·D M Kunis·M J Gutnick

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Abstract

Potassium-sensitive microelectrodes were used to study activity-dependent changes of extracellular potassium ion concentration ([K+]o) in rat optic nerves of different postnatal ages (1 day to adulthood). The maximum level to which [K+]o rose with optimal frequencies of stimulation depended on age: mean maximum evoked [K+]o was 17.2 microM in 1- to 3-day-old optic nerves and 9.8 microM in adult nerves. The ceiling [K+]o seen in immature optic nerves, which is uniquely large for a mammalian central nervous system structure, may result from a relatively enhanced rate of evoked K+ release.

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Aging Animals Animals, Newborn Electric Stimulation Evoked Potentials Neurons Optic Nerve Potassium Rats Journal Article Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S.

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B W Connors, B R Ransom, D M Kunis, M J Gutnick. 1982-06-18. Activity-dependent K+ accumulation in the developing rat optic nerve.. https://doi.org/10.1126/science.7079771

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