Tyrosine phosphorylation of the GluR2 subunit is required for long‐term depression of synaptic efficacy in young animals in vivo

Hippocampus - Tập 17 Số 8 - Trang 600-605 - 2007
Christopher J. Fox1, Kyle Russell1, Andrea K. Titterness1, Yu Tian Wang2,3, Brian R. Christie4,3,1
1the Neuroscience Program,
2Department of Physiology
3The Brain Research Centre
4Department of Psychology, The University of British Columbia, Vancouver, British Columbia

Tóm tắt

AbstractThe study of the intracellular mechanics that underlay changes in synaptic efficacy is a rapidly evolving field of research. It is currently believed that NMDA receptors play a significant role in the induction of synaptic plasticity, whereas AMPA receptors play a significant role in its expression. For AMPA receptors, it has been shown that tyrosine phosphorylation of the GluR2 carboxyl termini is required for the expression of long‐term depression of synaptic efficacy (LTD) in vitro (Ahmadian et al. (2004) EMBO J 23:1040–1050). In the present study, we sought to determine whether similar mechanisms are involved in vivo, where different stimulation parameters are required for the induction of LTD. We initially used a paired‐burst (PB) paradigm that reliably induces LTD in vivo. In these animals we were able to prevent the induction and expression of PB‐LTD by administering a peptide (GluR‐3Y) that acted as a competitive inhibitor of tyrosine phosphorylation. In a separate set of animals, we exposed animals to brief periods of stress (S) before using low‐frequency stimuli to induce LTD (S‐LTD). Again, GluR2–3Y blocked both the induction and expression of S‐LTD. In contrast, an inert version of the peptide, with alanine replacing the three tyrosine residues, did not inhibit LTD induction. In addition, we demonstrated that GluR2–3Y did not affect the induction of long‐term potentiation in vivo. These findings support the hypothesis that tyrosine phosphorylation and AMPA receptor endocytosis are necessary steps for the induction and maintenance of two forms of LTD in the CA1 region. © 2007 Wiley‐Liss, Inc.

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Tài liệu tham khảo

10.1016/0006-8993(96)00538-0

10.3109/10253899809167281

10.1038/sj.emboj.7600126

10.1523/JNEUROSCI.1905-05.2005

10.1038/361031a0

10.1038/nrn1556

10.1016/j.neuroscience.2003.09.029

10.1023/B:NERE.0000035805.46592.6c

10.1002/hipo.20230

10.1046/j.1365-2826.2001.00688.x

10.1016/0006-8993(94)91069-3

10.1073/pnas.0507572102

10.1126/science.1096615

10.1016/S0006-3223(98)00224-8

10.1111/j.1471-4159.1993.tb09839.x

10.1152/physrev.00014.2003

10.1146/annurev.neuro.25.112701.142758

10.1523/JNEUROSCI.1697-04.2004

10.1016/j.neuropharm.2006.07.005

10.1523/JNEUROSCI.17-12-04820.1997

10.1046/j.1471-4159.1994.63020596.x

10.1038/387497a0

10.1073/pnas.95.6.3204

Zhou JZ, 2000, Corticosterone impairs cultured hippocampal neurons and facilitates Ca2+ influx through voltage‐dependent Ca2+ channel, Acta Pharmacol Sin, 21, 156