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bioRxiv · 10.1101/2021.12.30.474558

BDNF-induced BDNF release mediates presynaptic LTP and is regulated by cannabinoids

Abstract

The brain-derived neurotrophic factor (BDNF) and its effector Tropomyosin receptor kinase B (TrkB) mediate diverse forms of activity-dependent synaptic plasticity implicated in learning, neural circuit refinement, and brain diseases, including epilepsy and mood disorders. Here, we report that activity-dependent release of presynaptic BDNF elicits the release of postsynaptic BDNF in a TrkB- and calcium-dependent manner. This BDNF-induced BDNF release was required for the induction of presynaptic long-term potentiation (LTP) of excitatory transmission in the mouse dentate gyrus. Tonic and phasic activity of presynaptic type-1 cannabinoid receptors suppressed BDNF release and dampened LTP, while exposure to enriched environment elicited BDNF-mediated LTP. In addition to mediating presynaptic plasticity, BDNF-induced BDNF release could be an important mechanism in synaptic stabilization during the maturation and refinement of neuronal connections. One-Sentence SummaryThe brain-derived neurotrophic factor induces its own release to mediate long-lasting increase in neurotransmitter release.

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BibTeXRIS

Berthoux, C., Nasrallah, K., Castillo, P. E.. 2021-12-30. BDNF-induced BDNF release mediates presynaptic LTP and is regulated by cannabinoids. https://doi.org/10.1101/2021.12.30.474558

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