[Functional characteristics of fructose-2,6-bisphosphate system in the liver during experimental streptozotocin diabetes].
The activity of phosphofructokinase-2, fructose, 1,6-bisphosphatase, glucokinase, and also the level of fructose 2,6-bisphosphate and glycogen were examined in the liver of normal, and streptozotocin-diabetic rats. It was shown that the activity of phosphofructokinase-2 was decreased in the liver of diabetic rats. Besides that the activity determined at pH 6.6 (the "active" or unphosphorylated enzyme form) was 3-fold reduced whereas the "total" enzyme activity as measured at pH 8.5 was lowered 1,7-fold. The phosphofructokinase-2 activity assay at two pH values allows to estimate a degree of phosphorylation of bifunctional enzyme which is markedly enhanced in diabetes. The fall of the bifunctional enzyme k in case activity is accompanied by the lowered fructose 2.6-bisphosphate level, increased fructose 1,6-bisphosphatase activity that in turn favours the liver tissue glycolysis inhibition and gluconeogenesis enhanced in diabetes.
Markova
M S
MS
Golubev
M A
MA
Gorodetskiĭ
V K
VK
Beliaeva
N F
NF
Viktorova
L N
LN
Korovkin
B F
BF
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D006597:Fructose-Bisphosphatase / Q000378:metabolism; D005635:Fructosediphosphates / Q000378:metabolism*; D008099:Liver / Q000378:metabolism*; D008112:Liver Glycogen / Q000378:metabolism; D008297:Male; D025481:Phosphofructokinase-2; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
D005635:Fructosediphosphates; D008112:Liver Glycogen; D017853:Phosphotransferases (Alcohol Group Acceptor); D025481:Phosphofructokinase-2; D006597:Fructose-Bisphosphatase
Nekotorye osobennosti funktsionirovaniia sistemy fruktozo-2,6-bisfosfata v tkani pecheni pri éksperimental'nom streptozototsinovom diabete.