LOWRI Flashcards
What do hepatocytes do in the liver?
buffer the potential hyperglycaemic effect of a carb load
How do hepatocytes do this? (1)
storing excess glucose by converting it to glycogen = glycogenesis
How do hepatocytes do this?
excess glucose —> glycogen
excess glucose —> fatty acids
fatty acids + glycerol = triglycerides
Glycogenolysis?
the biochemical breakdown of glycogen to glucose
Gluconeogenesis?
synthesis of new glucose from non-carb sources
Renal threshold for glucose?
11.1mmol/L
Renal function in relation to glucose: type of mechanism?
passive, but Na-dependent mechanism takes place in proximal tubule
Renal function in relation to glucose: what do the tubules do with glucose?
renal tubules absorb almost all glucose, filtered by the glomeruli, urinary glucose is normally undetectable
when does glycosuria occur?
when plasma levels exceed the renal threshold
The brain is dependent on glucose, but cells cannot…
store glucose, synthesis glucose, metabolise other substances (exception of ketones), extract glucose from extracellular fluid at low glucose concentrations
Reference ranges:
Plasma / serum glucose (fasting) = 3.5-5.5mmol/L
Plasma / serum glucose (random) = <10mmol/L
Urinary glucose = negative
Islet of Langerhans?
cells that we depend on to produce the relevant hormones to maintain glucose concentration
Beta cells?
production and release of insulin
comprises >60% of islet cells
Alpha cells?
production and release of glucagon
comprises around 30% of islet cells
how many delta cells, pancreatic polypeptide cells and ghrelin-secreting cells are islet cells?
comprises around 10% of islet cells
