Energy Storage Flashcards
(10 cards)
What are the possible substrates or gluconeogensis
- pyruvate, lactate and glycerol - converted to glucose
- essential and non amino acids
- acetyl~CoA cannot be converted into glucose! PDH is irreversible
Why can diabetes lead to increased severity of hyperglycaemia in terms of gluconeogensis
Inadequate insulin levels, alters the insulin:glucagon ration which affects fructose 1,6 bisphosphatase (insulin decreases, glucagon increases), and fructose 1,6 is one of the two major sites for gluconeogensis - it causes to skip stages 1-3 in glycolosis
Info about Triacylgycerols
Glycerol + fatty acids = trigs (esterified) lipolysis is the break down
Stored in anhydrous form - hydrophobic
Stored in specialised tissue - adipose
High effective as energy storage
Storage - promotes via insulin, reduced by glucagon, adrenaline, cortisol growth hormone and thyroxin
Aspects of fatty acid synthesis (lipogenesis)
Synthesised from acetyle~CoA (from mitochondria)
Required ATP and NADPH
Occurs in the cytoplasm of liver cells
Aspects of fatty acid oxidation
Cycle of relations that remove C2 C2 atoms removed at acetyle~CoA Produces acetyle~CoA Occurs in mitochondria Enzymes separate in mitochondria matrix Oxidative - produces NADH and FAD2H Requires small amount of ATP to activate fatty acid Intermediates are linked to CoA Glucagon and adrenaline stimulate Insulin inhibits
Aspects of fatty acid synthesis
Cole of relations that add C2 C2 atoms added as malonyl CoA Consumes acetyle~CoA Occurs in cytoplasm Reductive - requires NADPH Requires large amounts of ATP to drive process Intermediates are linked to fatty acid synthase Glucagon and adrenaline inhibit Insulin stimulates
What is the Amino acid pool and normal amounts
Total existing (intracellular and extracellular) free amino acids 70kg male =100g Fasting conc = 3mmol/l
What is nitrogen balance
Most nitrogen is from protein (90%)
Leaves in urea (85%), creatine (5%) and ammonia (3%)
Healthy - N in = N out
Pregnancy - N in > N out
Starvation - N in
What is measured in liver function test
Levels of ALT and AST
What are the major control sites of gluconeogensis
Fructose 1,6 - bisphosphatase - by pass steps 1-3 glycolosis
PEPCK - ATP and GTP hydrolysis - bypass step 10
