PMID- 8072844
OWN - NLM
STAT- MEDLINE
DCOM- 19940926
LR  - 20190726
IS  - 0031-6768 (Print)
IS  - 0031-6768 (Linking)
VI  - 427
IP  - 3-4
DP  - 1994 Jun
TI  - Effect of exercise on hexokinase distribution and mitochondrial respiration in 
      skeletal muscle.
PG  - 257-63
AB  - Horses were subjected to treadmill running at 65% (submaximal) or 100% (maximal) 
      VO2,max to examine the effects of exercise on subcellular distribution of 
      hexokinase (HK) and on mitochondrial respiration. It is hypothesized that the 
      fraction of HK bound to mitochondria will be reduced due to an elevation of 
      glucose-6-phosphate (G-6-P) concentration in the exercising muscle and that such 
      release of HK from mitochondria will depress oxidative phosphorylation. Changes 
      in muscle G-6-P concentration, pH, subcellular HK distribution, mitochondrial 
      respiration and other metabolites were determined in biopsy samples pre-exercise, 
      immediately post-exercise and during the recovery phase. The fraction of HK 
      associated with mitochondria decreased from 38% to 7% at the end of maximal 
      exercise; exercise at VO2,max also reduced respiratory capacity of muscle 
      homogenates by 20% and was associated with a fivefold increase in muscle [G-6-P], 
      a potent agent known to dissociate HK from mitochondria. The HK distribution 
      returned to normal within 60 min after exercise and the reassociation of the HK 
      with mitochondria parallelled the removal of muscle G-6-P. No changes in muscle 
      HK distribution and respiration were found following the submaximal exercise 
      despite the fact that G-6-P was slightly elevated. Muscle concentrations of 
      adenosine triphosphate, creatine phosphate and glycogen and pH dropped after 
      exercise while lactate concentration increased. The amount of mitochondria-bound 
      HK was also altered in vitro in a preparation of mitochondria isolated from rat 
      skeletal muscle to examine the effect of the bound HK on mitochondrial 
      respiration.(ABSTRACT TRUNCATED AT 250 WORDS)
FAU - Chen, J
AU  - Chen J
AD  - Department of Veterinary and Comparative Anatomy, Pharmacology, College of 
      Veterinary Medicine, Pullman, WA 99164-6520.
FAU - Gollnick, P D
AU  - Gollnick PD
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Germany
TA  - Pflugers Arch
JT  - Pflugers Archiv : European journal of physiology
JID - 0154720
RN  - 0 (Glucosephosphates)
RN  - 0 (Lactates)
RN  - 020IUV4N33 (Phosphocreatine)
RN  - 33X04XA5AT (Lactic Acid)
RN  - 56-73-5 (Glucose-6-Phosphate)
RN  - 8L70Q75FXE (Adenosine Triphosphate)
RN  - 9005-79-2 (Glycogen)
RN  - EC 2.7.1.1 (Hexokinase)
RN  - I38ZP9992A (Magnesium)
SB  - IM
MH  - Adenosine Triphosphate/metabolism
MH  - Animals
MH  - Glucose-6-Phosphate
MH  - Glucosephosphates/metabolism
MH  - Glycogen/metabolism
MH  - Hexokinase/*metabolism
MH  - Horses
MH  - Hydrogen-Ion Concentration
MH  - Lactates/metabolism
MH  - Lactic Acid
MH  - Magnesium/physiology
MH  - Male
MH  - Mitochondria, Muscle/drug effects/enzymology/*metabolism
MH  - Oxygen Consumption
MH  - Phosphocreatine/metabolism
MH  - Physical Exertion/*physiology
MH  - Rats
MH  - Rats, Sprague-Dawley
EDAT- 1994/06/01 00:00
MHDA- 1994/06/01 00:01
CRDT- 1994/06/01 00:00
PHST- 1994/06/01 00:00 [pubmed]
PHST- 1994/06/01 00:01 [medline]
PHST- 1994/06/01 00:00 [entrez]
AID - 10.1007/BF00374532 [doi]
PST - ppublish
SO  - Pflugers Arch. 1994 Jun;427(3-4):257-63. doi: 10.1007/BF00374532.