Cortical Tagged Synaptic Long-Term Depression in the Anterior Cingulate Cortex of Adult Mice
- 1Center for Neuron and Disease, Frontier Institute of Science and Technology, Xi’an Jiaotong University, Xi’an 710049, China
- 2Zhuomin Institute of Brain Research, Qingdao International Academician Park, Qingdao 266000, China
- 3CAS Key Laboratory of Brain Connectome and Manipulation, Interdisciplinary Center for Brain Information, The Brain Cognition and Brain Disease Institute, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
- 4Department of Exercise & Health Science, Xi'an Physical Education University, Xi'an 710068, China
- 5Department of Physiology, Faculty of Medicine, University of Toronto, Toronto, Ontario M5S 1A8, Canada
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Author contributions: X.-H.L. and M.Z. designed research; W.L. performed research; W.L. contributed unpublished reagents/analytic tools; W.L. analyzed data; W.L., Q.-Y.C., and Z.Z. wrote the paper.
Abstract
The anterior cingulate cortex (ACC) is a key cortical region for pain perception and emotion. Different forms of synaptic plasticity, including long-term potentiation (LTP) and long-term depression (LTD), have been reported in the ACC. Synaptic tagging of LTP plays an important role in hippocampus-related associative memory. In this study, we demonstrate that synaptic tagging of LTD is detected in the ACC of adult male and female mice. This form of tagged LTD requires the activation of metabotropic glutamate receptor subtype 1 (mGluR1). The induction of tagged LTD is time-related with the strongest tagged LTD appearing when the interval between two independent stimuli is 30 min. Inhibitors of mGluR1 blocked the induction of tagged LTD; however, blocking N-methyl-d-aspartate receptors did not affect the induction of tagged LTD. Nimodipine, an inhibitor of L-type voltage–gated calcium channels, also blocked tagged LTD. In an animal model of amputation, we found that tagged LTD was either reduced or completely blocked. Together with our previous report of tagged LTP in the ACC, this study strongly suggests that excitatory synapses in the adult ACC are highly plastic. The biphasic tagging of synaptic transmission provides a new form of heterosynaptic plasticity in the ACC which has functional and pathophysiological significance in phantom pain.
- anterior cingulate cortex
- long-term depression
- metabotropic glutamate receptor subtype 1
- multielectrode array
- synaptic tagging
- Received January 5, 2024.
- Revision received July 2, 2024.
- Accepted July 5, 2024.
- Copyright © 2024 the authors
