Hexose metabolism in pancreatic islets UDP-glucose pyrophosphorylase activity.
UDP-glucose pyrophosphorylase was measured in rat pancreatic islets, the generation of D-glucose 1-phosphate from UDP-glucose and PPI being eventually coupled to the generation of L-[U-14C]glutamate from 14C-labelled alpha-ketoglutarate. The activity of the enzyme was about one order of magnitude lower in islet than liver homogenates. The affinity of the enzyme for either UDP-glucose or PPi was comparable, however, in liver and islets. The activity of UDP-glucose pyrophosphorylase was somewhat lower in islets from animals with inherited or acquired diabetes mellitus than in those from control rats. These findings are considered in connection with the accumulation of glycogen in islets of hyperglycemic animals.
Zhang
T M
TM
Laboratory of Experimental Medicine, Erasmus Medical School, Brussels Free University, Belgium.
Giroix
M H
MH
Sener
A
A
Malaisse
W J
WJ
D000818:Animals; D002250:Carbon Radioisotopes; D003921:Diabetes Mellitus, Experimental / Q000201:enzymology*; D011756:Diphosphates / Q000378:metabolism; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism; D006601:Hexoses / Q000378:metabolism; D007515:Islets of Langerhans / Q000201:enzymology*; D008099:Liver / Q000201:enzymology*; D051381:Rats; D011919:Rats, Inbred Strains; D017208:Rats, Wistar; D012016:Reference Values; D013379:Substrate Specificity; D005957:UTP-Glucose-1-Phosphate Uridylyltransferase / Q000378:metabolism*; D014532:Uridine Diphosphate Glucose / Q000378:metabolism
D002250:Carbon Radioisotopes; D011756:Diphosphates; D006601:Hexoses; D018698:Glutamic Acid; D005957:UTP-Glucose-1-Phosphate Uridylyltransferase; D014532:Uridine Diphosphate Glucose