Anatomical and functional characterization of fear-activated oxytocin neurons
Final Report Abstract
Based on the results of our study, we hypothesize that the central OT system is composed of functionally specialized ensembles of magnocellular OT neurons, which modulate CeA network activity and, subsequently, fear expression and extinction in a context-dependent manner. Importantly, the process of fear learning induces plastic changes in axons of magnocellular OT neurons, resulting in a switch from OT to glutamate signaling in the CeA. Furthermore, we here identified a population of parvocellular OT neurons, which seems to be part of a fixed fear circuit and orchestrates magnocellular OT activity to modulate OT release upon demand. However, in addition to the neuromodulation of fear behavior, functional changes also occurred in the neurohormonal component of the OT system: massive OT release into the blood could potentially attenuate the overactivation of the hypothalamic-pituitary-adrenal axis, decrease blood pressure, stimulate lipogenesis, release insulin and glucagon as well as protect pancreatic beta cells. Altogether, the elevation of peripheral OT levels can be considered as an adaptive mechanism for homeostatic coping with deleterious stress event.
Publications
- (2019) A Fear Memory Engram and Its Plasticity in the Hypothalamic Oxytocin System. Neuron 103 (1) 133-146.e8
Hasan, Mazahir T.; Althammer, Ferdinand; Da Silva Gouveia, Miriam; Goyon, Stephanie; Eliava, Marina; Lefevre, Arthur; Kerspern, Damien; Schimmer, Jonas; Raftogianni, Androniki; Wahis, Jerome; Knobloch-Bollmann, H. Sophie; Tang, Yan; Liu, Xinying; Jain, Ap
(See online at https://doi.org/10.1016/j.neuron.2019.04.029) - (2016): A new population of parvocellular oxytocin neurons controlling magnocellular neuron activity and inflammatory pain processing. Neuron 89: 1291-1304
Eliava, M., Melchior, M., Knobloch-Bollmann, H.S., Wahis, J., da Silva Gouveia, Tang, Y., Ciobanu, A.C., Triana del Rio, R., Roth, L.C., Althammer, F., Chavant, V., Goumon, Y., Gruber, T., Busnelli, M., Chini, B., Tan, L., Mitre, M., Froemke, R.C., Chao, M.V., Giese, G., Sprengel, R., Kuner, R., Poisbeau, P., Seeburg, P.H., Stoop, R., Charlet, A., Grinevich V.
(See online at https://doi.org/10.1016/j.neuron.2016.01.041)
