Cerebral mitochondrial redox states during metabolic stress in the immature rat.
The brain mitochondrial NAD+/NADH ratio, as a reflection of the oxidation-reduction (redox) state of cellular compartment, was determined under conditions of hypoxia, anoxia, hypoxia-ischemia, complete ischemia and hypoglycemia in immature rats. NAD+/NADH ratios were calculated from changes in the concentrations of specific oxidative substrates and calculated intracellular pH during cerebral metabolic stress. The results suggest that the use of the acetoacetate/beta-hydroxybutyrate substrate couple provides a more accurate prediction of the mitochondrial redox state under adverse conditions than use of the alpha-ketoglutarate/glutamate couple. It is possible that the mitochondrial oxidation seen with the latter substrate couple during cerebral metabolic stress might reflect a population of cells (neurons or glia) which are substrate-deprived relative to the rest of the brain in the setting of metabolic stress produced by oxygen deficiency.
Vannucci
R C
RC
Department of Pediatrics (Pediatric Neurology), Pennsylvania State University College of Medicine, Milton S. Hershey Medical Center, Hershey 17033.
Brucklacher
R M
RM
D020155:3-Hydroxybutyric Acid; D000090:Acetoacetates / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn / Q000378:metabolism*; D001921:Brain / Q000378:metabolism*; D001927:Brain Diseases / Q000378:metabolism; D002545:Brain Ischemia / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism; D006885:Hydroxybutyrates / Q000378:metabolism; D007003:Hypoglycemia / Q000378:metabolism; D000860:Hypoxia / Q000378:metabolism; D007656:Ketoglutaric Acids / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism*; D009243:NAD / Q000378:metabolism; D010084:Oxidation-Reduction; D051381:Rats; D017207:Rats, Sprague-Dawley; D013312:Stress, Physiological / Q000378:metabolism*
D000090:Acetoacetates; D006885:Hydroxybutyrates; D007656:Ketoglutaric Acids; D009243:NAD; D018698:Glutamic Acid; C016635:acetoacetic acid; D020155:3-Hydroxybutyric Acid