-transparent.png){kind=logo}
Previous studies demonstrate that nonexercising muscle may serve as a source of lactate for hepatic gluconeogenesis during long-term exercise. The concentration of fructose 2,6-diphosphate (F-2,6-P2), a signal molecule that accelerates glycolysis, was examined in liver and muscles of fed and fasted resting rats and in fasted rats run for 5, 15, or 30 min at 21 m/min (15% grade). Liver F-2,6-P2 decreased in response to fasting and exercise. White quadriceps (composed predominantly of type IIb fibers) F-2,6-P2 increased from 2.2 +/- 0.1 to 4.5 +/- 0.4 pmol/mg in the fasted rats in response to 30 min of treadmill running. No increase was observed in the red region of the quadriceps (composed of type IIa fibers). The fasted rats also exhibited a threefold increase in glucose 1,6-diphosphate (G-1,6-P2) in the white quadriceps after 30 min of exercise, whereas no significant changes were observed in the red quadriceps or in liver. The increases in F-2,6-P2 and G-1,6-P2 may be important in accelerating glycolysis and enhancing lactate production in muscles that are not glycogen depleted during long-term exercise.
W W Winder, and
S R Fisher, and
S P Gygi, and
J A Mitchell, and
E Ojuka, and
D A Weidman
June 1992,
The American journal of physiology,
W W Winder, and
S R Fisher, and
S P Gygi, and
J A Mitchell, and
E Ojuka, and
D A Weidman
December 1989,
Biochemical and biophysical research communications,
W W Winder, and
S R Fisher, and
S P Gygi, and
J A Mitchell, and
E Ojuka, and
D A Weidman
April 1989,
Medicine and science in sports and exercise,
W W Winder, and
S R Fisher, and
S P Gygi, and
J A Mitchell, and
E Ojuka, and
D A Weidman
January 1989,
Bulletin et memoires de l'Academie royale de medecine de Belgique,
W W Winder, and
S R Fisher, and
S P Gygi, and
J A Mitchell, and
E Ojuka, and
D A Weidman
January 1988,
Acta gastro-enterologica Belgica,
W W Winder, and
S R Fisher, and
S P Gygi, and
J A Mitchell, and
E Ojuka, and
D A Weidman
February 1996,
Clinical biochemistry,
W W Winder, and
S R Fisher, and
S P Gygi, and
J A Mitchell, and
E Ojuka, and
D A Weidman
January 1994,
Klinicheskaia laboratornaia diagnostika,
W W Winder, and
S R Fisher, and
S P Gygi, and
J A Mitchell, and
E Ojuka, and
D A Weidman
January 1983,
Bulletin et memoires de l'Academie royale de medecine de Belgique,
W W Winder, and
S R Fisher, and
S P Gygi, and
J A Mitchell, and
E Ojuka, and
D A Weidman
October 1984,
The American journal of physiology,
W W Winder, and
S R Fisher, and
S P Gygi, and
J A Mitchell, and
E Ojuka, and
D A Weidman
March 1985,
The American journal of physiology,
