Effects of fatty acid oxidation on glucose utilization by isolated hepatocytes.
We have studied the inhibitory action of long- and short-chain fatty acids on hepatic glucose utilization in hepatocytes isolated from fasted rats. The rates of hepatic glucose phosphorylation and glycolysis were determined from the tritiated products of [2-3H] and [6-3H]glucose metabolism, respectively. The difference between these was taken as an estimate of the 'cycling' between glucose and glucose-6-phosphate. In the presence of 40 mM glucose this cycling was estimated at 0.68 mumol/min/g wet wt. Glucose phosphorylation was unaffected during palmitate and hexanoate oxidation to ketone bodies but glycolysis was inhibited. The rate of glucose cycling was increased during this phase to 1.25 mumol/min/g. Following the complete metabolism of the fatty acids, glycolysis was reinstated and cycling rates returned to control levels. Hepatic glucose cycling appears to be an important component of the glucose/fatty acid cycle.
Berry
M N
MN
Department of Medical Biochemistry, School of Medicine, Flinders University of South Australia, Adelaide.
Phillips
J W
JW
Henly
D C
DC
Clark
D G
DG
D000818:Animals; D005227:Fatty Acids / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D006003:Glycogen / Q000378:metabolism; D006019:Glycolysis; D007657:Ketone Bodies / Q000378:metabolism; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D008297:Male; D010084:Oxidation-Reduction; D019308:Palmitic Acid; D010169:Palmitic Acids / Q000378:metabolism; D010766:Phosphorylation; D051381:Rats; D017208:Rats, Wistar; D014316:Tritium
D005227:Fatty Acids; D007657:Ketone Bodies; D010169:Palmitic Acids; D014316:Tritium; D019308:Palmitic Acid; D006003:Glycogen; D005947:Glucose