Glucose and lactate are equally effective in energizing activity-dependent synaptic vesicle turnover in purified cortical neurons

This study examines the role of glucose and lactate as energy substrates to sustain synaptic vesicle cycling. Synaptic vesicle turnover was assessed in a quantitative manner by fluorescence microscopy in primary cultures of mouse cortical neurons. An electrode-equipped perfusion chamber was used to...

Full description

Saved in:

Bibliographic Details
Published in:	Neuroscience Vol. 141; no. 1; pp. 157 - 165
Main Authors:	Morgenthaler, F.D., Kraftsik, R., Catsicas, S., Magistretti, P.J., Chatton, J.-Y.
Format:	Journal Article
Language:	English
Published:	Oxford Elsevier Ltd 01-01-2006 Elsevier
Subjects:	Animals Biological and medical sciences Cells, Cultured Cerebral Cortex - cytology Chi-Square Distribution Diagnostic Imaging - methods Dose-Response Relationship, Drug Drug Interactions Embryo, Mammalian energy metabolism fluorescence microscopy Fluorescent Antibody Technique - methods Fundamental and applied biological sciences. Psychology glucose Glucose - pharmacology lactate Lactic Acid - pharmacology Mice neurometabolic coupling Neurons - cytology Neurons - drug effects Neurons - physiology Neurons - radiation effects Potassium - pharmacology Pyridinium Compounds - pharmacokinetics Quaternary Ammonium Compounds - pharmacokinetics synaptic vesicle turnover Synaptic Vesicles - drug effects Synaptic Vesicles - metabolism Time Factors Vertebrates: nervous system and sense organs synaptic vesicle turnover glucose neurometabolic coupling FM1-43 lactate MTBS fluorescence microscopy ROI energy metabolism Lactates Energy metabolism Neuron Turnover Synaptic vesicle Glucose
Online Access:	Get full text
Tags:	Add Tag No Tags, Be the first to tag this record!

Description
Summary:	This study examines the role of glucose and lactate as energy substrates to sustain synaptic vesicle cycling. Synaptic vesicle turnover was assessed in a quantitative manner by fluorescence microscopy in primary cultures of mouse cortical neurons. An electrode-equipped perfusion chamber was used to stimulate cells both by electrical field and potassium depolarization during image acquisition. An image analysis procedure was elaborated to select in an unbiased manner synaptic boutons loaded with the fluorescent dye N-(3-triethylammoniumpropyl)-4-(4-(dibutylamino)styryl)pyridinium dibromide (FM1-43). Whereas a minority of the sites fully released their dye content following electrical stimulation, others needed subsequent K+ depolarization to achieve full release. This functional heterogeneity was not significantly altered by the nature of metabolic substrates. Repetitive stimulation sequences of FM1-43 uptake and release were then performed in the absence of any metabolic substrate and showed that the number of active sites dramatically decreased after the first cycle of loading/unloading. The presence of 1 mM glucose or lactate was sufficient to sustain synaptic vesicle cycling under these conditions. Moreover, both substrates were equivalent for recovery of function after a phase of decreased metabolic substrate availability. Thus, lactate appears to be equivalent to glucose for sustaining synaptic vesicle turnover in cultured cortical neurons during activity.
Bibliography:	ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23
ISSN:	0306-4522 1873-7544
DOI:	10.1016/j.neuroscience.2006.03.065