Glucose utilization by Kupffer cells, endothelial cells, and granulocytes in endotoxemic rat liver

Abstract

There are several types of glucose-consuming, immunologically active nonparenchymal cells interspersed among the glucose-producing parenchymal liver cells. Combining the in vivo 2-deoxyglucose tracer technique with cell separation methods enabled us to investigate the effect of Escherichia coli endotoxin on the rate of glucose utilization by the nonparenchymal cells. Rats were injected with [14C]deoxyglucose, and intracellular 2-deoxyglucose 6-phosphate was determined in different liver cell fractions. Parenchymal, Kupffer, and endothelial cells as well as polymorphonuclear leukocytes (PMN) were separated from the liver by centrifugal elutriation followed by Ficoll-Hypaque density gradient. The number of PMN obtained from the liver was increased severalfold 3 h after endotoxin and was comparable to the number of Kupffer cells. Glucose utilization by the liver of fasted rats was due predominantly to nonparenchymal cells. Endotoxin enhanced the rate of glucose utilization by Kupffer (6.7-fold) and endothelial (2.7-fold) cells and by the infiltrated hepatic PMN (5.4-fold). Enhanced glucose metabolism of immunologically active cells is part of the hepatic immune response and subserves the antibacterial defense of the body. The activated cells, however, may also have the potential of causing tissue damage by releasing harmful toxic metabolites.