Serotonin facilitates synaptic plasticity in kitten visual cortex: an in vitro study

doi:10.1016/S0165-3806(97)00083-7

Developmental Brain Research

Volume 101, Issues 1–2, July 1997, Pages 299-304

https://doi.org/10.1016/S0165-3806(97)00083-7 Get rights and content

Abstract

We have addressed the role of serotonin-2C (5-HT_2C) receptors in the development and maintenance of synaptic plasticity in the kitten visual cortex. In visual cortical slices, taken from 40- to 80-day-old kittens, bath application of serotonin markedly facilitated the induction of both long-term depression (LTD) and long-term potentiation (LTP). Field potential responses to white matter stimulation were recorded from layer IV after a regime of low frequency stimulation (LFS; 1 Hz, 15 min), which reliably induced LTP or LTD in younger kittens (less than 30 days of age). At 40–80 days, this protocol almost never induced LTD or LTP in layer IV. However, in 50% of the visual cortical slices studied in 40–80-day-old kittens, LTD or LTP was induced, if serotonin (1 or 10 μM) was co-applied with LFS. No such serotonin facilitation of long-term plasticity was ever detected in >120-day-old animals, indicating that serotonin facilitates synaptic plasticity within a defined period of visual cortical development. Serotonergic 5-HT_2C receptors are likely to contribute to the synaptic plasticity observed in layer IV, since mesulergine, an antagonist of the 5-HT_2C receptor, completely blocked synaptic modifications induced by the combination of low frequency stimulation and serotonin application.

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Acknowledgements

We wish to thank Virginia Booth for valuable technical assistance. This research was supported by Natural Sciences and Engineering Research Council of Canada and Medical Research Council of Canada.

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Short communicationSerotonin facilitates synaptic plasticity in kitten visual cortex: an in vitro study

Abstract

Section snippets

Acknowledgements

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