Effects of hypothermic deep-anaesthesia on energy metabolism at brain and peripheral levels: a multi-probe microdialysis study in free-moving rat.
Reduction of central energy metabolism is a strategy to protect brain against neurotoxic events. The aim of this microdialysis study in rats is to evaluate changes in energy metabolite levels at central level (striatum) comparatively to peripheral level (subcutaneous adipose tissue) during hypothermic barbituric deep-anaesthesia (sodium pentobarbital 60 mg/kg intraperitoneally). At brain level, extracellular glucose increases (+14.9%) while lactate decreases (-16.6%); opposite results were observed at subcutaneous level (-29.2% for glucose and +68.3% for lactate). Lactate/pyruvate ratio remains unchanged at brain level, but increases at subcutaneous level (+73.5%). In light of previous studies on the effects of pentobarbital on regional blood flow and tissue glucose consumption, our data correlates the fact that pentobarbital reduces preferentially brain energetic metabolism. We suggest that those regional effects are explained, at least for a part, by the fact that central isoform glucose transporters (Glut1 and Glut3) are known to be more sensitive to pentobarbital than peripheral isoforms. Such facts can be involved in the protection of brain tissue against ischemic risk due to decreased cerebral blood flow decrease.
Lonjon
M
M
Service de Neurochirurgie, CHU Pasteur, 30 Avenue de la voie Romaine, UNSA, 06002 CEDEX 01, (Groupe de Neurobiologie Fondamentale et Clinique), Nice, France. lonjon.m@chu-nice.fr
Risso
J J
JJ
Palmier
B
B
Negrin
J
J
Darbin
O
O
D000759:Adjuvants, Anesthesia / Q000494:pharmacology*; D000818:Animals; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D004734:Energy Metabolism / Q000187:drug effects / Q000502:physiology; D005947:Glucose / Q000378:metabolism*; D007036:Hypothermia, Induced; D019344:Lactic Acid / Q000378:metabolism*; D008297:Male; D017551:Microdialysis / Q000379:methods; D010424:Pentobarbital / Q000494:pharmacology*; D019289:Pyruvic Acid / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley
D000759:Adjuvants, Anesthesia; D019344:Lactic Acid; D019289:Pyruvic Acid; D010424:Pentobarbital; D005947:Glucose