% IMPORTANT: The following is UTF-8 encoded. This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.
@ARTICLE{Cremer:10474,
author = {Cremer, C.M. and Bidmon, H.-J. and Görg, B. and
Palomero-Gallagher, N. and Lopez Escobar, J. and Speckmann,
E.-J. and Zilles, K.},
title = {{I}nhibition of glutamate/glutamine cycle in vivo results
in decreased benzodiazepine binding and differentially
regulated {GABA}ergic subunit expression in the rat brain},
journal = {Epilepsia},
volume = {51},
issn = {0013-9580},
address = {Oxford [u.a.]},
publisher = {Wiley-Blackwell},
reportid = {PreJuSER-10474},
pages = {1446 - 1455},
year = {2010},
note = {This study was partially supported by a grant of the
Helmholtz Alliance in "Mental Health in an Ageing Society."
We thank S. Buller, L. Igdalova, and S. Wilms for their
excellent technical assistance.},
abstract = {The astrocytic enzyme glutamine synthetase (GS) is a key
regulator of glutamate and γ-aminobutyric acid (GABA)
metabolism in the glutamate/glutamine cycle (GGC).
Inhibition of GS results in changes of neurotransmitter
release and recycling. However, little is known about the
influence of GGC on neurotransmitter receptor expression. In
the pentylenetetrazole model of epilepsy, GS becomes
nitrated and partially inhibited, and we demonstrated
alterations of neurotransmitter receptor expression in the
same model. Therefore, we hypothesized similar changes of
neurotransmitter receptor expression when GS is inhibited in
vivo.Rats were treated with a single dose (100 mg/kg
bodyweight) of l-methionine sulfoximine (MSO), an
irreversible inhibitor of GS. We used ³H-receptor
autoradiography to measure glutamatergic
[α-amino-3-hydroxy-5-methyl-4-isoxazol-propionic acid
(AMPA), kainate, N-methyl-D-aspartate (NMDA)], GABAergic
(GABA(A) , GABA(B) and GABA(A) -associated benzodiazepine
(BZ) binding sites], dopamine D₁, and adenosine A₁
receptor subtypes. In addition, we performed saturation
analysis of BZ binding sites on cerebral membrane
homogenates and investigated the expression of GABA(A) α₁
and γ₂ subunits (which primarily mediate BZ binding) by
western blot analysis.We demonstrated a significant
reduction of BZ binding in the somatosensory, piriform, and
entorhinal cortices and in the amygdala, 24 and 72 h after
MSO treatment. Saturation analysis revealed decreased BZ
binding (B(max)) on cerebral membrane homogenates 72 h after
MSO treatment, without changes in binding site affinity
(K(D)). Furthermore, we found differential changes of α₁
, γ₂ , and phosphorylated γ₂ subunits following MSO
treatment.On the basis of our findings, we conclude that the
glutamate/glutamine cycle directly influences GABAergic
neurotransmission by regulating GABA(A) subunit composition,
thereby affecting its modulation by endogenous
benzodiazepines.},
keywords = {Animals / Autoradiography: methods / Benzodiazepines:
metabolism / Binding Sites: drug effects / Brain: anatomy
$\&$ histology / Brain: drug effects / Brain: metabolism /
Drug Interactions / Enzyme Inhibitors: pharmacology /
Excitatory Amino Acid Antagonists: pharmacology /
Glutamate-Ammonia Ligase: metabolism / Glutamic Acid:
metabolism / Glutamine: metabolism / Male / Methionine
Sulfoximine: pharmacology / Protein Binding: drug effects /
Protein Subunits: genetics / Protein Subunits: metabolism /
RNA, Messenger: metabolism / Rats / Rats, Wistar /
Receptors, GABA: genetics / Receptors, GABA: metabolism /
Time Factors / Tritium: metabolism / Enzyme Inhibitors (NLM
Chemicals) / Excitatory Amino Acid Antagonists (NLM
Chemicals) / Protein Subunits (NLM Chemicals) / RNA,
Messenger (NLM Chemicals) / Receptors, GABA (NLM Chemicals)
/ Tritium (NLM Chemicals) / Benzodiazepines (NLM Chemicals)
/ Methionine Sulfoximine (NLM Chemicals) / Glutamine (NLM
Chemicals) / Glutamic Acid (NLM Chemicals) /
Glutamate-Ammonia Ligase (NLM Chemicals) / J (WoSType)},
cin = {INM-2 / JARA-BRAIN},
ddc = {610},
cid = {I:(DE-Juel1)INM-2-20090406 / $I:(DE-82)080010_20140620$},
pnm = {Funktion und Dysfunktion des Nervensystems (FUEK409) /
89571 - Connectivity and Activity (POF2-89571)},
pid = {G:(DE-Juel1)FUEK409 / G:(DE-HGF)POF2-89571},
shelfmark = {Clinical Neurology},
typ = {PUB:(DE-HGF)16},
pubmed = {pmid:20384720},
UT = {WOS:000280669600013},
doi = {10.1111/j.1528-1167.2010.02562.x},
url = {https://juser.fz-juelich.de/record/10474},
}