arne1's version from 2015-09-18 01:19


Question Answer
Gluconeogenesisglucose from non-carbs. in liver and renal cortex. during fasting or fight and flight
Ativator of gluconeogenesisglucagon and cortisol
inhibitor of gluconeogenesisinsulin
enzymes of irreversible steps of glycolysisGlucokinase (in liver), PFK-1, Pyruvate kinase
enzymes of irreversible steps of gluconeogenesisG-6-P (in liver and kidney), Fru-1,6-bisphosphatase, Pyruvate carboxylase, PEP carboxykinase
Glucose-6-phosphatase is found inliver and kidney. needed to form free glucose from Glu-6
Lactate is provided bymuscle and RBC used for gluconeogenesis
Alanine (and glutamine) is provided bymuscle and other cells used for gluconeogenesis
hepatocytes and lactatelactate is converted to pyruvate via lactate dehydrogenase (NAD+ is reduced to NADH as coenzyme). this reaction is reversible and also happens in the RBCs.
Alanine in hepatocytes is converted topyruvate. needs alpha-ketoglutarate and alanine aminotransferase plus pyridoxal phosphate (PLP) as a coenzyme.
Alanine and glutamine are high duringfasting. transported to liver for urea cycle.
Phosphoenolpyruvate carboxykinase (PEPCK) or PEPgluconeogenesis enzyme. converts oxaloacetate into phosphoenolpyruvate and CO2. in cytosol and mitos
pyruvate kinase glycolysis step isirreversible
Only in liver pyruvate kinase can bephosphorylated and Inactivated
Gluconeogenesis occurs atlow insulin/glucagon ratio
Fructose 1,6-bisphosphatase in hepatic gluconeogenesis is inhibited byAMP and Fructose 2,6-bisphosphate
Energy requirements for gluconeogenesisglucose synth from 2 pyruvates costs 4 ATP and 2 GTP and 2 NADH
Gluconeogenesis occurs fromalanine, glutamine, lactate, glycerol, free fatty acids