PMID- 8983983
OWN - NLM
STAT- MEDLINE
DCOM- 19970103
LR  - 20210107
IS  - 0014-4819 (Print)
IS  - 0014-4819 (Linking)
VI  - 106
IP  - 3
DP  - 1995
TI  - NMDA and non-NMDA receptors mediate taste afferent inputs to cortical taste 
      neurons in rats.
PG  - 391-402
AB  - Two main subclasses of ionotropic receptors for excitatory amino acids (EAAs), 
      N-methyl-D-aspartate (NMDA) receptors and non-NMDA receptors, are involved in 
      neurotransmission in the cortex of mammals. To examine whether EAAs are 
      transmitters at the cortical taste area (CTA) in rats and to elucidate which 
      types of the two ionotropic receptors operate at these synapses, we studied the 
      effects of microiontophoretic administration of EAA antagonists on the responses 
      of 64 taste cortical neurons to four basic taste stimuli in urethane-anesthetized 
      rats. Both D-2-amino-5-phosphonovalerate (APV), a selective antagonist for NMDA 
      receptors, and 6-cyano-7-nitro-quinoxaline-2,3-dione (CNQX), a selective 
      antagonist for non-NMDA receptors, suppressed most of the taste responses. The 
      percentage of neurons suppressed by APV (70.3%) was almost the same as that 
      suppressed by CNQX (64.1%). These suppressive effects were independent of the 
      effects of background discharges during the prestimulus, water-rinsing period. 
      The percentage of neurons suppressed by the antagonists did not differ between 
      any pairs of taste stimuli. The number of neurons possessing both receptors was 
      larger in the granular insular area (area GI), one of the two CTAs, than in the 
      dysgranular insular area (area DI). In addition, taste responses were suppressed 
      by CNQX or by both APV and CNQX in area GI in a significantly larger number of 
      layer V neurons than in area DI. The present results indicate that normal 
      excitatory transmission of taste afferents in the CTA in rats was mediated by 
      both NMDA and non-NMDA receptors. The finding that a large fraction of neurons in 
      the CTA in rats mediated taste information through NMDA receptors in normal 
      transmission might be related to the higher potency of the plasticity observed in 
      the CTA.
FAU - Otawa, S
AU  - Otawa S
AD  - Department of Physiology, Kumamoto University School of Medicine, Japan.
FAU - Takagi, K
AU  - Takagi K
FAU - Ogawa, H
AU  - Ogawa H
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Germany
TA  - Exp Brain Res
JT  - Experimental brain research
JID - 0043312
RN  - 0 (Excitatory Amino Acid Antagonists)
RN  - 0 (Receptors, Glutamate)
RN  - 0 (Receptors, N-Methyl-D-Aspartate)
RN  - 6384-92-5 (N-Methylaspartate)
RN  - 6OTE87SCCW (6-Cyano-7-nitroquinoxaline-2,3-dione)
RN  - 76726-92-6 (2-Amino-5-phosphonovalerate)
RN  - SIV03811UC (Kainic Acid)
SB  - IM
MH  - 2-Amino-5-phosphonovalerate/pharmacology
MH  - 6-Cyano-7-nitroquinoxaline-2,3-dione/pharmacology
MH  - Animals
MH  - Cerebral Cortex/cytology/*physiology
MH  - Electrophysiology
MH  - Excitatory Amino Acid Antagonists/pharmacology
MH  - Kainic Acid/pharmacology
MH  - N-Methylaspartate/pharmacology
MH  - Neurons/*physiology
MH  - Neurons, Afferent/drug effects/*physiology
MH  - Rats
MH  - Rats, Sprague-Dawley
MH  - Receptors, Glutamate/*physiology
MH  - Receptors, N-Methyl-D-Aspartate/*physiology
MH  - Stimulation, Chemical
MH  - Taste/*physiology
EDAT- 1995/01/01 00:00
MHDA- 1995/01/01 00:01
CRDT- 1995/01/01 00:00
PHST- 1995/01/01 00:00 [pubmed]
PHST- 1995/01/01 00:01 [medline]
PHST- 1995/01/01 00:00 [entrez]
AID - 10.1007/BF00231062 [doi]
PST - ppublish
SO  - Exp Brain Res. 1995;106(3):391-402. doi: 10.1007/BF00231062.