AJP - Endocrinology and Metabolism, Vol 240, Issue 6 640-E644, Copyright © 1981 by American Physiological Society
Alloxan action on glucose metabolism in cultured fibroblasts. I. Stimulation and inhibition of glucose utilization
F. Ishibashi, H. Hidaka, R. M. Fields, B. V. Howard and P. H. Bennett
The influence of alloxan on mammalian cell glucose metabolism has been
investigated using human diploid fibroblastic cells in culture. When cell
monolayers were exposed to D-[14C]glucose, the presence of alloxan
(0.31-1.87 mM) resulted initially in a dose-dependent enhancement of total
cell glucose incorporation. This was observed within 2 min and declined by
6 min. After that time, alloxan inhibited glucose incorporation. When
hexose transport was examined directly using glucose analogues, alloxan
neither enhanced nor inhibited the uptake of 3-O-methylglucose or
2-deoxyglucose. Alloxan exerted no effect on cell permeability or cell
viability. These results suggest that alloxan may directly influence cell
glucose metabolism beyond the level of phosphorylation. The dual effect of
alloxan on glucose incorporation may be related to the alloxan stimulation
and subsequent inhibition of glucose-induced insulin release in pancreatic
islets.
