PMID- 18723120
OWN - NLM
STAT- MEDLINE
DCOM- 20090615
LR  - 20090302
IS  - 1532-0456 (Print)
IS  - 1532-0456 (Linking)
VI  - 149
IP  - 3
DP  - 2009 Apr
TI  - Characterization of ionotropic glutamate receptors in insect neuro-muscular 
      junction.
PG  - 275-80
LID - 10.1016/j.cbpc.2008.07.010 [doi]
AB  - Pharmacological properties of ionotropic glutamate receptors from Calliphora 
      vicina larvae neuro-muscular junction (C. vicina iGlurs) were studied by 
      two-electrode voltage-clamp technique. Characteristics of the ion channel pore 
      were analyzed using a 26-member series of channel blockers, which includes mono- 
      and dicationic derivatives of adamantane and phenylcyclohexyl. Structure-activity 
      relationships were found to be markedly similar to the Ca2+-permeable AMPA 
      receptors (AMPAR) but not NMDA receptors (NMDAR) channel subtype seen in 
      vertebrates. Like AMPARs the channels of C. vicina iGlurs are sensitive mainly to 
      dicationic compounds with 6-7 spacers between hydrophobic headgroup and terminal 
      aminogroup. Study of the voltage dependence of block demonstrated that, like 
      AMPARs, the C. vicina iGlur channels, are permeable to organic cations with 
      dimensions exceeding 10 A. Concentration dependence of block suggests the 
      presence of two distinct channel populations with approximately 20-fold different 
      sensitivity to cationic blockers. The recognition domain properties are more 
      complex. Besides glutamate, the channels can be activated by kainate, quisqualate 
      and domoate. Competitive antagonists of AMPAR and NMDAR are virtually inactive 
      against the C. vicina iGlurs as well as allosteric modulators GYKI 52466 and 
      PEPA. Surprisingly, the responses were potentiated 3 times by 100 mkM of 
      cyclothiazide. We conclude that the channel-forming domain of C. vicina iGlurs is 
      AMPAR-like, whereas the recognition domain is specific.
FAU - Fedorova, I M
AU  - Fedorova IM
AD  - I.M. Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 
      St-Petersburg, Russia.
FAU - Magazanik, L G
AU  - Magazanik LG
FAU - Tikhonov, D B
AU  - Tikhonov DB
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20080731
PL  - United States
TA  - Comp Biochem Physiol C Toxicol Pharmacol
JT  - Comparative biochemistry and physiology. Toxicology & pharmacology : CBP
JID - 100959500
RN  - 0 (Excitatory Amino Acid Antagonists)
RN  - 0 (Insect Proteins)
RN  - 0 (Receptors, AMPA)
RN  - 0 (Receptors, N-Methyl-D-Aspartate)
SB  - IM
MH  - Animals
MH  - Binding Sites
MH  - Diptera/*metabolism
MH  - Dose-Response Relationship, Drug
MH  - Excitatory Amino Acid Antagonists/chemistry/metabolism/pharmacology
MH  - Excitatory Postsynaptic Potentials
MH  - Insect Proteins/antagonists & inhibitors/chemistry/*metabolism
MH  - Larva/metabolism
MH  - Molecular Conformation
MH  - Neuromuscular Junction/drug effects/embryology/*metabolism
MH  - Patch-Clamp Techniques
MH  - Protein Structure, Tertiary
MH  - Receptors, AMPA/antagonists & inhibitors/chemistry/*metabolism
MH  - Receptors, N-Methyl-D-Aspartate/metabolism
MH  - Structure-Activity Relationship
EDAT- 2008/08/30 09:00
MHDA- 2009/06/16 09:00
CRDT- 2008/08/30 09:00
PHST- 2008/06/04 00:00 [received]
PHST- 2008/07/28 00:00 [revised]
PHST- 2008/07/29 00:00 [accepted]
PHST- 2008/08/30 09:00 [pubmed]
PHST- 2009/06/16 09:00 [medline]
PHST- 2008/08/30 09:00 [entrez]
AID - S1532-0456(08)00143-9 [pii]
AID - 10.1016/j.cbpc.2008.07.010 [doi]
PST - ppublish
SO  - Comp Biochem Physiol C Toxicol Pharmacol. 2009 Apr;149(3):275-80. doi: 
      10.1016/j.cbpc.2008.07.010. Epub 2008 Jul 31.