the liver Flashcards
what does the liver devote its pathways to
the needs of other tissues
why does the liver store glucose as glycogen
to meet the needs of other tissues
how do hepatocytes respond to metabolic signals from the blood
by altering the flux through carbohydrates , lipids and protein pathways
what does glucagon promote
phosphorylation of enzymes via cAMP
what transporters take glucose in and out of the liver
GLUT 2 transporters
what do GLUT transporters rely on
a concentration gradient
what metabolic pathways in carbohydrate metabolism are connected to the liver
glucose-> glycogen (glycogenesis)
glycogen->glucose (glycogenolysis)
glucose->pyruvate (glycolysis)
pyruvate->glucose (gluconeogenesis)
citrate->oxaloacetate(TCA cycle)
what happens when there is a fall in blood glucose
there is low glycogen/insulin
hepatocytes increase glycogenolysis and gluconeogenesis
what happens when there is a rise in blood glucose
high insulin/glucagon
hepatocytes increase glycogenesis and glycolysis
what happens during a well fed state
glucokinase
isozyme of hexokinase
synthesis of glucokinase is increased by insulin
what happens to glucokinase in the liver
it is inhibited by F-6-P
what does F-6-P promote
the binding of a liver specific regulatory protein to glucokinase
what do rising levels of G-6-P lead to
increased glycogen synthesis and glycogen synthase
what does glycogen synthase increasing promote
the dephosphorylation of glycogen synthase
what enzyme has the greatest impact on glycolytic flux
6-phosphofructo-1-kinase
