Metabolism and diabetes mellitus Flashcards
Blood glucose control is dependent on what status?
Nutritional
When is insulin released, before or after a meal?
After, as blood glucose levels rise
What is stimulated by insulin?
Uptake and utilisation of glucose by cells
What three chemicals are released several hours after a meal as blood glucose levels fall?
Glucagon, cortisol, and adrenaline
What processes are stimulated as blood glucose levels fall several hours after a meal?
- Glycogenolysis
- Gluconeogenesis
- Glucose is released from the liver
What pathways are stimulated when insulin signals the fed state?
Cellular uptake and storage
Which pathways are inhibited when insulin signals the fed state?
Fuel breakdown
List the four processes that occur when insulin signals the fed state
- Uptake of fuel substrates into some cells (muscle, adipose tissue)
- Storage of fuels (lipids, glycogen)
- Inhibits gluconeogenesis
- Biosynthesis of macromolecules (proteins, DNA)
Glucose utilisation causes BSL to fall to normal; what is the result of this?
Insulin secretion falls
Which pathwas are stimulated when glucagon signals the fasted state?
Fuel breakdown
Which pathways are inhibited when glucagon signals the fasted state?
Cellular uptake and storage
List the five processes that occur when glucagon signals the fasted state
- Increasing glycogen breaking/inhibiting glycogen synthesis
- Inhibiting fuel storage (lipids, proteins)
- Stimulates gluconeogenesis
- Enhances ketogenesis in liver (ketone body production from fatty acids)
- Promotes protein breakdown in liver (does not effect muscle protein)
Between meals, ____ is released from the pancreas
Glucagon
Between meals, adipose tissues breaks down triglycerides into ____ ____ and ____.
Fatty acids; glycerol
Between meals, skeletal muscle is broken down to ____ ____.
Amino acids
What happens to the amino acids broken down from skeletal muscle when between meals?
The liver converts them to glucose which is exported to the blood
Between meals, the liver converts excess fatty acids to ____
Ketones
The brain can use ____% ketones during starvation
60%
Following a meal, ____ is released from the pancreas
Insulin (in response to a detected rise in BGL)
Following a meal, all tissues use ____ as an energy source.
Glucose
Following a meal, adipose tissues converts excess glucose to ____ ____ and then to ____.
Fatty acids; triglycerides
Following a meal, skeletal muscle converts excess glucose to ____.
Glycogen
Following a meal, the liver converts excess glucose and protein to glycogen, and further excess to ____ ____ and ____ to be transported to adipose tissue for storage.
Fatty acids; triglycerides
Following a meal, ____ ____ are used for tissue building and repair.
Amino acids
What is the meaning of ‘diabetes mellitus’?
Sweet urine — BGL is so high it overwhelms the ability of the kidneys to hold onto glucose so it is secreted in urine
In simple terms, diabetes mellitus is due to…
Lack of insulin secretion, action, or both