Link to bioRxiv paper: http://biorxiv.org/cgi/content/short/2020.04.15.042788v1?rss=1 Authors: Noriega-Prieto, J. A., Maglio, L. E., Maroto, I. B., Martin-Cortecero, J., Munoz-Callejas, A., Callejo-Mostoles, M., Fernandez de Sevilla, D. Abstract: Insulin-like growth factor-1 (IGF-1) plays a key role in synaptic plasticity, degenerative diseases, spatial learning, and anxiety-like behavioral processes. While IGF-1 regulates neuronal activity in many areas of the brain, its effect on synaptic plasticity and animal behavior dependent on the prefrontal cortex remain unexplored. Here, we show that IGF-1 induces a long-lasting depression of the medium and slow post-spike afterhyperpolarization (mAHP and sAHP), increasing the excitability of layer 5 pyramidal neurons of the infralimbic cortex. Besides, IGF-1 mediates a long-term depression of both inhibitory and excitatory synaptic transmission that results in a long-term potentiation of the postsynaptic potentials. We demonstrate that these synaptic and intrinsic regulatory processes mediated by IGF-1 favor the fear extinction memory. These results show novel functional consequences of IGF-1 signaling on animal behavior tasks dependent on the prefrontal cortex, revealing IGF-1 as a key element in the control of the fear extinction memory. Copy rights belong to original authors. Visit the link for more info