diabetes quiz Flashcards
summarise normal glucose homeostasis *
depends on insulin secretion from teh pancreas
insulin secreted in response to meal
insulin signasl to cells around body that they should start using glucose - especially muscle and liver
insulin turns on the glut 4 pump - glut4 is sat inside membrane and comes to surface and therefore glucose enters cells
small amount of insulin is very potent because a lot of fat and lipid cells
k and phosphate
describe insulin *
signal that you have been fed
switches on all pathways that use up glucose adn store glycogen as fat
glycogen synthase is turned on
glycolysis in liver and muscle is turned on
stimulates fat generation
suppress ketone production
gluconeogenesis is switched off - this is where new glucose is made by insulin- alanine amino transferase (ALT) is the enzyme that does this
what happens to insulin during starvation *
levels fall
what substrates are available during starvation *
glucose
glycogen
TG - not converted to glucose, fa used as fuel - good source of energy
protein - only for survival, become weak
what is switched on during satrvation *
insulin levels are low but not zero
glyccogenolysis - liver glycogen stores last <24hours
liver switches on ketogenesis becasue fa cant cross the bbb - so need ketones for survival - this ketone production is turned on by insulin - there will be ketones in the urine
if have 0 insulin make way more ketones than you need
what type of insulin deficiency is type 1 and 2 dm *
type 1 - absolute
type 2- relative
describe the pathology of t1dm *
immune system destroys the islets of langerhans in the pancreas - immune system meant to kkill the virus taht expresses b cell marker but also kills the b cell
resultant total def of insulin
all cells fail to take up glucose glut4 not switched on
plasma glucose rises
glucose leaks into urine
therefore have polyuria and polydipsia
complete insulin def causes acidosis
what happens when insulin levels are 0 *
liver behaves as if no fuel for brain to work so makes huge levels of ketones
blood turns acidic with all the ketones
the brain cannot function in an acid ph - become unconscious
describe diabetic ketoacidosis *
blood glucose high becasue cant get into cells
blood full of ketones - acids
severe dehydration
air hunger - slow deep respiration - kussmaul’s breathing is the way to get rid of co2 body is causing resp alkalosis to counteract the metabolic acidosis
How do you manage dka *
rehydrate with saline
iv insulin - problem is becasue there is no insulin so use insulin to treat it - try to stop the production of ketones
what is teh treatment of t1dm *
insulin
diet and reduce the risk factors for retinopathy, nephropathy, and neuropathy
describe the pathology of t2dm *
insulin doenst work effectively - only some glucose enters the cell
insulin turns of ketogenesis - no ketones present
pancreas increase insulin secretion because not getting a response
eventually panc exhausted so get t2dm
dont become very sick because have dont have ketones - dont present with dka
phenotype of t2 diabetics *
usually older - mature onset
usually obese
non insulin dependant
not prone to ketoacidosis
no hla associations ]no islet ab
100 % concordance between monozygouys twins
manage with diet/oral hypoglycaemic agents
very high glucose
glucose slowly rises causing polyuria and polydipsia thirsty pts drink sweet drinks
develop hyper osmolar non ketotoc coma (HONCK) - didnt know had dm and are suddenly uncoscious and dehhydrated, more likely to die than with dka because older - have been dehydrated for 3 months for eg, so if rehydrate quickly they get brain oedema
how would you manage HONKC *
rehydrate with normal saline slowly
if you go to fast cause a shift in the electrolytes = cerebal oedema = death
how do you manage t2dm *
lose weight
avoid sugar
high fibre diet to cause slow absorption of carbohydrate
make yourself more sensitive to insulin - metformin which is a biguanide
insulin/drugs that stimulate the pancreas more ie sulphonylureas like gliclazide
use secretagogues - substance that causes something else to be excreted