When there is high levels of glucose in the blood?
Pancrease produces insulin
Increase glycogen synthesis in liver and increase glucose uptake into cells.
Glucose now falls down to normal range
When there is a low level of glucose in the body?
Stimulates the secretion of glucagon from the paancreas
This increases the glycogen breakdown to glucose in the liver
Rising the glucose levels back to normal
Glucagon opposes many of the regulatory effecst of insulin through its own secondary messenger cAMP.
Breakdown of glycogen into glucose in the liver
Schematic of glucagon action
See additional sheet
What hormones are activated when there is a decrease in blood glucose levels?
What hormones are produced when there is a high blood glucose level?
What does glucagon do to the futile cycling?
Induces phosphorylation of FBPase-2
Therefore higher F6P than F26P
No longer is the gluconeogenesis suppresses
Most common of all endocrine disorders
Hyperglycaemia is the major feature of this condition.
There is a high extracellular glucose level but a intracellular glucose deficiency
Increase in blood glucose levels
Glucose in the urine with large osmotic diuresis
ie. high glucose concentration for the volume of water.
Looks very concentrated- like it would if you were dehydrated and has a sweet taste due to the high levels of glucose
What are the two WHO tests to test for diabetes?
FPG: the basal blood glucose levels: need to be >7mmol/l
OGTT: fast the patient and then dose them with 75g of glucose and see how long it takes them to dispose of glucose. Should be equal or greater than 11.1mmol/l after 2hrs
What are two WHO criteria for diabetes?
IGT: impaired glucose tolerance. FPG comes back below 9mmol/l, OGTT is greater tha 8.7 but lower than 11.1.
IFG: impaired fasting glucose: FBG (fasting blood glucose level) between 6.1 and 7mmol/l
What are IGT and IFG sufferers at risk of?
What are the FBG and OGTT levels during pregnancy?
Diagnosis test for diabetes
diabetes will be >6.5% while people with pre-diabetes will have between 5.7-6.4%
Type 1 diabetes definition?
It is when the pancreatic beta cells are destroyed and no longer can produce insulin.
Insulin is required for survival.
Usually characterised by the presence of anti-GAD (anti-islet cell antibodies)
Type 2 diabetes definiution?
Only when they dont have T1, monogenic or other medical condition that is suggestive of secondary diabetes.
90% of the sufferers of T2 are obese.
It is when there is enough insulin in the body but the cells are no responsive to them
Maturity onset diabetes of the young.
When there is a mutation in a single gene of the diabetic person that effect insulin (either production or effect)
MODY: is the most common mutation in the HNF1A gene.
Secondary causes of diabetes?
eg. drugs, pancreatic pathology, endocrine cause.
When does this happen?
Elevated levels of lipids in the blood plasma.
Happens if the person have T2DM.
Insulin no longer suppresses hormonal expression therefore always high levels of VLDL expression causing the lipoprotein lipase to constantly converted glucose into fatty acids and glycerol
What are the 3 different forms of MODY diabetes?
65% are transcription factors mutations- progressive- no sudden onset
20% are glucokinase mutations- relatively stable.
15% are due to MODYX mutation