PMID- 1314516
OWN - NLM
STAT- MEDLINE
DCOM- 19920521
LR  - 20171213
IS  - 0002-9513 (Print)
IS  - 0002-9513 (Linking)
VI  - 262
IP  - 4 Pt 2
DP  - 1992 Apr
TI  - Oxidative and glycolytic pathways in rat (newborn and adult) and turtle brain: 
      role during anoxia.
PG  - R595-603
AB  - Using enzyme histochemistry and in vitro electrophysiological recordings in brain 
      slices, we studied 1) the relative activity of cytochrome c oxidase (Cytox) and 
      hexokinase (HK) and 2) cellular function by examining ionic homeostasis across 
      cell membranes in the turtle and newborn (5 days old) and adult rat central 
      nervous system. We found that Cytox was higher in the rostral than in the caudal 
      brain regions of the adult rat and that the activity in the newborn is at least 
      as high as in the adult rat. In contrast, adult turtles had very low Cytox 
      activity throughout the central nervous system. Compared with that in the adult 
      rat, HK activity in the newborn was generally lower in the rostral brain and 
      cerebellum but similar or higher in the brain stem and spinal cord. In the 
      turtle, HK activity was higher in the cerebellum, brain stem, and ventral horn of 
      the spinal cord than in those in the rat. During anoxia, extracellular K+ 
      increased by approximately 10-fold (from 3.2 to approximately 32 mM) in the adult 
      brain stem but only by 2.6 mM in newborn rats. After glycolysis was blocked with 
      iodoacetic acid (10-20 mM), extracellular K+ increased remarkably in both adult 
      and newborn rats to approximately 35 mM. In contrast, the turtle brain tissue 
      showed a slight and insignificant increase in extracellular K+ during complete 
      anoxia or with iodoacetic acid; there was a modest increase in K+ when anoxia and 
      iodoacetate were administered together. We conclude that 1) the newborn rat brain 
      must rely either on higher glycolytic capacity or on a reduction of metabolic 
      rate during O2 deprivation and 2) the turtle brain can subsist on nonglucose 
      fuels or on fuels not requiring the citric acid cycle and the electron transfer 
      chain.
FAU - Xia, Y
AU  - Xia Y
AD  - Department of Pediatrics, Yale University School of Medicine, New Haven, 
      Connecticut 06510.
FAU - Jiang, C
AU  - Jiang C
FAU - Haddad, G G
AU  - Haddad GG
LA  - eng
GR  - HD-15736/HD/NICHD NIH HHS/United States
GR  - HL-39924/HL/NHLBI NIH HHS/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, P.H.S.
PL  - United States
TA  - Am J Physiol
JT  - The American journal of physiology
JID - 0370511
RN  - 0 (Iodoacetates)
RN  - EC 1.9.3.1 (Electron Transport Complex IV)
RN  - EC 2.7.1.1 (Hexokinase)
RN  - WF5188V710 (Iodoacetic Acid)
SB  - IM
MH  - Aging/*metabolism
MH  - Animals
MH  - Animals, Newborn/growth & development/*metabolism
MH  - Brain/enzymology/*metabolism
MH  - Electron Transport Complex IV/metabolism
MH  - Glycolysis/*physiology
MH  - Hexokinase/metabolism
MH  - Hypoxia/*metabolism
MH  - Iodoacetates/pharmacology
MH  - Iodoacetic Acid
MH  - Oxidation-Reduction
MH  - Rats
MH  - Rats, Inbred Strains
MH  - Turtles/metabolism
EDAT- 1992/04/01 00:00
MHDA- 1992/04/01 00:01
CRDT- 1992/04/01 00:00
PHST- 1992/04/01 00:00 [pubmed]
PHST- 1992/04/01 00:01 [medline]
PHST- 1992/04/01 00:00 [entrez]
AID - 10.1152/ajpregu.1992.262.4.R595 [doi]
PST - ppublish
SO  - Am J Physiol. 1992 Apr;262(4 Pt 2):R595-603. doi: 
      10.1152/ajpregu.1992.262.4.R595.