PMID- 22707377
OWN - NLM
STAT- MEDLINE
DCOM- 20130627
LR  - 20121121
IS  - 1098-1063 (Electronic)
IS  - 1050-9631 (Linking)
VI  - 22
IP  - 12
DP  - 2012 Dec
TI  - Frequency dependency of NMDA receptor-dependent synaptic plasticity in the 
      hippocampal CA1 region of freely behaving mice.
PG  - 2238-48
LID - 10.1002/hipo.22041 [doi]
AB  - Hippocampal synaptic plasticity in the form of long-term potentiation (LTP) and 
      long-term depression (LTD) is likely to enable synaptic information storage in 
      support of memory formation. The mouse brain has been subjected to intensive 
      scrutiny in this regard; however, a multitude of studies has examined synaptic 
      plasticity in the hippocampal slice preparation, whereas very few have addressed 
      synaptic plasticity in the freely behaving mouse. Almost nothing is known about 
      the frequency or N-methyl-D-aspartate receptor (NMDAR) dependency of hippocampal 
      synaptic plasticity in the intact mouse brain. Therefore, in this study, we 
      investigated the forms of synaptic plasticity that are elicited at different 
      afferent stimulation frequencies. We also addressed the NMDAR dependency of this 
      phenomenon. Adult male C57BL/6 mice were chronically implanted with a stimulating 
      electrode into the Schaffer collaterals and a recording electrode into the 
      Stratum radiatum of the CA1 region. To examine synaptic plasticity, we chose 
      protocols that were previously shown to produce either LTP or LTD in the 
      hippocampal slice preparation. Low-frequency stimulation (LFS) at 1 Hz (900 
      pulses) had no effect on evoked responses. LFS at 3 Hz (ranging from 200 up to 2 
      x 900 pulses) elicited short-term depression (STD, <45 min). LFS at 3 Hz (1,200 
      pulses) elicited slow-onset potentiation, high-frequency stimulation (HFS) at 100 
      Hz (100 or 200 pulses) or at 50 Hz was ineffective, whereas 100 Hz (50 pulses) 
      elicited short-term potentiation (STP). HFS at 100 Hz given as 2 x 30, 2 x 50, or 
      4 x 50 pulses elicited LTP (>24 h). Theta-burst stimulation was ineffective. 
      Antagonism of the NMDAR prevented STD, STP, and LTP. This study shows for the 
      first time that protocols that effectively elicit persistent synaptic plasticity 
      in the slice preparation elicit distinctly different effects in the intact mouse 
      brain. Persistent LTD could not be elicited with any of the protocols tested. 
      Plasticity responses are NMDAR dependent, suggesting that these phenomena are 
      relevant for hippocampus-dependent learning.
CI  - Copyright (c) 2012 Wiley Periodicals, Inc.
FAU - Buschler, Arne
AU  - Buschler A
AD  - Department of Neurophysiology, Medical Faculty, Ruhr University Bochum, Bochum, 
      Germany.
FAU - Goh, Jinzhong Jeremy
AU  - Goh JJ
FAU - Manahan-Vaughan, Denise
AU  - Manahan-Vaughan D
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20120618
PL  - United States
TA  - Hippocampus
JT  - Hippocampus
JID - 9108167
RN  - 0 (Receptors, N-Methyl-D-Aspartate)
SB  - IM
MH  - Animals
MH  - CA1 Region, Hippocampal/*physiology
MH  - Electric Stimulation
MH  - Electrodes, Implanted
MH  - Evoked Potentials/physiology
MH  - Male
MH  - Mice
MH  - Mice, Inbred C57BL
MH  - Neuronal Plasticity/*physiology
MH  - Receptors, N-Methyl-D-Aspartate/*metabolism
EDAT- 2012/06/19 06:00
MHDA- 2013/06/29 06:00
CRDT- 2012/06/19 06:00
PHST- 2012/05/10 00:00 [accepted]
PHST- 2012/06/19 06:00 [entrez]
PHST- 2012/06/19 06:00 [pubmed]
PHST- 2013/06/29 06:00 [medline]
AID - 10.1002/hipo.22041 [doi]
PST - ppublish
SO  - Hippocampus. 2012 Dec;22(12):2238-48. doi: 10.1002/hipo.22041. Epub 2012 Jun 18.