PMID- 12367599
OWN - NLM
STAT- MEDLINE
DCOM- 20021224
LR  - 20190726
IS  - 0028-3908 (Print)
IS  - 0028-3908 (Linking)
VI  - 43
IP  - 4
DP  - 2002 Sep
TI  - Complex effects of CNQX on CA1 interneurons of the developing rat hippocampus.
PG  - 523-9
AB  - We have investigated the effect of the 
      alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor 
      antagonist, 6-cyano-7-nitro-quinoxaline-2,3-dione (CNQX), on spontaneous GABA(A) 
      receptor-mediated transmission in the hippocampal CA1 subfield. On average, 
      simultaneous recordings from CA1 str. radiatum interneurons and pyramidal cells 
      showed that CNQX application doubled the frequency of bicuculline sensitive 
      spontaneous inhibitory postsynaptic currents (sIPSCs) without apparently changing 
      their amplitude. However, despite the increase in sIPSC frequency, current-clamp 
      recording showed that CNQX application was sufficient in most cases to depolarize 
      interneurons to firing threshold. In contrast, CNQX application could not induce 
      firing in pyramidal cells. In the presence of tetrado-toxin (TTX), CNQX increased 
      interneuron membrane conductance, and depolarized interneurons from resting 
      potentials. The axons of the studied interneurons ramify widely in the CA1 region 
      and suggest that the cells of our sample are mostly involved with control of 
      dendritic excitability. Our results indicate that CNQX-induced increase of sIPSC 
      frequency is not limited to excitatory cells, but also impacts GABAergic 
      interneurons. However, despite the increase of sIPSC frequency, CNQX-induced 
      depolarization is sufficient to selectively generate firing in interneurons and 
      thus modify the network properties mediated by GABA(A) receptors in the 
      hippocampus.
FAU - Maccaferri, G
AU  - Maccaferri G
AD  - Department of Physiology, Tarry Bldg, Rm 5-707 M211, 303 E. Chicago Ave., IL 
      60611, USA. g-maccaferri@northwestern.edu
FAU - Dingledine, R
AU  - Dingledine R
LA  - eng
GR  - R01 MH067561/MH/NIMH NIH HHS/United States
GR  - R01 MH067561-01/MH/NIMH NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - England
TA  - Neuropharmacology
JT  - Neuropharmacology
JID - 0236217
RN  - 0 (Excitatory Amino Acid Antagonists)
RN  - 0 (GABA Antagonists)
RN  - 6OTE87SCCW (6-Cyano-7-nitroquinoxaline-2,3-dione)
RN  - H030S2S85J (Kynurenic Acid)
RN  - Y37615DVKC (Bicuculline)
SB  - IM
MH  - 6-Cyano-7-nitroquinoxaline-2,3-dione/*pharmacology
MH  - Animals
MH  - Axons/drug effects/physiology
MH  - Bicuculline/pharmacology
MH  - Electrophysiology
MH  - Excitatory Amino Acid Antagonists/*pharmacology
MH  - Excitatory Postsynaptic Potentials/drug effects
MH  - GABA Antagonists/pharmacology
MH  - Hippocampus/*cytology/drug effects/*growth & development
MH  - Image Processing, Computer-Assisted
MH  - In Vitro Techniques
MH  - Interneurons/*drug effects/ultrastructure
MH  - Kynurenic Acid/pharmacology
MH  - Membrane Potentials/physiology
MH  - Nerve Net/drug effects
MH  - Patch-Clamp Techniques
MH  - Pyramidal Cells/drug effects
MH  - Rats
MH  - Rats, Sprague-Dawley
EDAT- 2002/10/09 04:00
MHDA- 2002/12/27 04:00
CRDT- 2002/10/09 04:00
PHST- 2002/10/09 04:00 [pubmed]
PHST- 2002/12/27 04:00 [medline]
PHST- 2002/10/09 04:00 [entrez]
AID - S0028390802001612 [pii]
AID - 10.1016/s0028-3908(02)00161-2 [doi]
PST - ppublish
SO  - Neuropharmacology. 2002 Sep;43(4):523-9. doi: 10.1016/s0028-3908(02)00161-2.