Oxytocin during early brain development
– Netherlands Institute for Neuroscience (Amsterdam), invited by R. Cossart

11 a.m.

Abstract: Spontaneous network activity occurs before birth and during early postnatal brain development. This type of activity regulates the establishment of synaptic connections and subcellular compartments in order to prepare the brain before it can fully experience the environment. How it can be affected by the action of neuromodulators remains poorly understood. Combining in vivo and in vitro, Ca2+ imaging and electrophysiology approaches, we addressed the role of oxytocin (OT) on spontaneous neuronal activity of primary visual cortex (V1). OT decreased strongly the network spontaneous activity of V1 when compare to somatosensory cortex (S1). Consistently with this observation, OT increased the frequency of V1 IPSCs, but it had a balanced effect in S1, increasing the frequency of both IPSCs and EPSCs. OT-induced inhibition was mediated by the activation of OT receptors in somatostatin interneurons (SST). OT depolarized V1 SST interneurons increasing their excitability and affecting its single action potential features. Together, our results reveal that OT exerts specific cellular and network effects in the developing V1, changing the inhibitory-excitatory balance towards inhibition.