Microdialysis monitoring of extracellular glutamate combined with the simultaneous recording of evoked field potentials in hippocampal organotypic slice cultures.
These experiments combined extracellular electrophysiological multirecordings from hippocampal organotypic slice cultures with application of drugs to and sampling of extracellular fluid from a restricted region of the slice using a microdialysis probe. Glutamate (Glu) concentrations were monitored in 0.5 or 2 min microdialysis samples, while evoked field potentials responses (EvFPR) in the CA1 region of the hippocampus (stimulation in the CA3 area) were simultaneously recorded using a multi-electrodes array (Physiocard). Glu was assayed by capillary electrophoresis with laser-induced fluorescence detection combined with a continuous flow derivatization of dialysates. The performance of this combined approach was demonstrated by monitoring extracellular Glu concentrations and EvFPR after K+ induced depolarisation, Glu uptake blockade by trans-pyrrolidine-2,4-dicarboxylic acid (PDC), and electrical stimulation. Such an approach allows a global monitoring of the neuronal functioning with a fine time resolution (up to 30 s) on a simple in vitro brain slice model, to be used as a complement to conventional in vivo microdialysis studies.
Robert
F
F
Département de Pharmacologie, Centre Médical Universitaire, Geneva, Switzerland. frobert@cmu.unige.ch
Parisi
L
L
Bert
L
L
Renaud
B
B
Stoppini
L
L
D000818:Animals; D003998:Dicarboxylic Acids / Q000494:pharmacology; D004594:Electrophysiology / Q000295:instrumentation / Q000379:methods; D005071:Evoked Potentials / Q000187:drug effects; D018698:Glutamic Acid / Q000032:analysis / Q000378:metabolism*; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D017551:Microdialysis / Q000295:instrumentation / Q000379:methods; D008839:Microelectrodes; D014179:Neurotransmitter Uptake Inhibitors / Q000494:pharmacology; D009924:Organ Culture Techniques; D011188:Potassium / Q000494:pharmacology; D011759:Pyrrolidines / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
D003998:Dicarboxylic Acids; D014179:Neurotransmitter Uptake Inhibitors; D011759:Pyrrolidines; D018698:Glutamic Acid; C083486:pyrrolidine-2,4-dicarboxylic acid; D011188:Potassium