Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
Concentration-dependent isoflurane effects on depolarization-evoked glutamate and GABA outflows from mouse brain slices
Autore:
Liachenko, S; Tang, P; Somogyi, GT; Xu, Y;
Indirizzi:
UnivAPittsburgh, Dept Anaesthesiol & Crit Care Med, Pittsburgh, PA 15261 US Univ Pittsburgh Pittsburgh PA USA 15261 Care Med, Pittsburgh, PA 15261 US Univ Pittsburgh, Dept Pharmacol, Pittsburgh, PA 15261 USA Univ PittsburghPittsburgh PA USA 15261 armacol, Pittsburgh, PA 15261 USA
Titolo Testata:
BRITISH JOURNAL OF PHARMACOLOGY
fascicolo: 1, volume: 127, anno: 1999,
pagine: 131 - 138
SICI:
0007-1188(199905)127:1<131:CIEODG>2.0.ZU;2-S
Fonte:
ISI
Lingua:
ENG
Soggetto:
RAT CEREBRAL-CORTEX; UPTAKE INHIBITOR L-TRANS-PYRROLIDINE-2,4-DICARBOXYLATE; VOLATILE ANESTHETICS; GENERAL-ANESTHETICS; CELLULAR MECHANISMS; AMINO-ACIDS; RELEASE; TRANSPORTER; SYNAPTOSOMES; MODULATION;
Keywords:
GABA; glutamate; isoflurane; evoked release; re-uptake; concentration-response curve; L-trans-pyrrolidine-2,4-dicarboxylic acid; nipecotic acid; brain slice; general anaesthetic;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Life Sciences
Citazioni:
45
Recensione:
Indirizzi per estratti:
Indirizzo: Xu, Y Univ,Pittsburgh, Dept Anaesthesiol & Crit Care Med, W-1358 Biomed Sci Tower Univ Pittsburgh W-1358 Biomed Sci Tower Pittsburgh PA USA 15261 ower
Citazione:
S. Liachenko et al., "Concentration-dependent isoflurane effects on depolarization-evoked glutamate and GABA outflows from mouse brain slices", BR J PHARM, 127(1), 1999, pp. 131-138

Abstract

1 The synaptic concentrations of glutamate and gamma-aminobutyric acid (GABA) are modulated by their release and re-uptake. The effects of general anaesthetics on these two processes remain unclear. This study evaluates the effects of isoflurane, a clinically important anaesthetic, on glutamate andGABA release and re-uptake in superfused mouse cerebrocortical slices.2 Experiments consisted of two 1.5-min exposures to 40 mM KCl in 30 min intervals. During the second exposure, different concentrations of isofluranewith and without 0.3 mM L-transpyrrolidinene-2,4-dicarboxylic acid (PDC, acompetitive inhibitor of glutamate uptake transporter) or I mM nipecotic acid (a competitive inhibitor of GABA uptake transporter) were introduced. The ratios of the second to first KCl-evoked increases in glutamate and GABAwere used to determine the isoflurane concentration-response curves.3 The results can be described as a sum of two independent processes, corresponding to the inhibitions of release and re-uptake, respectively. The ECS, values for the inhibitions of release and re-uptake were 295+/-16 and 805+/-43 mu M for glutamate, and 229+/-13 and 520+/-25 mu M for GABA, respectively. Addition of PDC did not significantly affect glutamate release but shifted the re-uptake curve to the left (EC50=315+/-20 mu M). Nipecotic acidcompletely blocked GABA uptake, rendering isoflurane inhibition of GABA re-uptake undetectable.4 Our data suggest that isoflurane inhibits both the release and re-uptakeof neurotransmitters and that the inhibitions occur at different EC50's. For GGBA, both EC50's are within the clinical concentration range. The net anaesthetic effect on extracellular concentrations of neurotransmitters, particularly GABA, depends on the competition between inhibition of release and that of re-uptake.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 30/11/20 alle ore 16:13:17