Chapter 3 Fasting state Flashcards
In the fasting state what do the levels in the blood look like
⬇️glucose
⬇️insulin
⬆️Glucagon
What occurs in the fasting state
Glucagon is high Glycogen breakdown Fat utilization Protein breakdown Brain uses glucose Muscle uses fat
The fasting state is also known as
Basal state
When does the fasting state occur
This state occur several hours after the last meal
What secrete glucagon when the glucose and insulin levels drop
The pancreas secrete glucagon
What happens when the pancreas secretes glucagon
Once the glucagon has been secreted this induces the liver to break down stored glycogen into free glucose
Pancreas secretes Glucagon➡️liver breaks down glycogen to glucose➡️
Once the glucose has been freed the glucose leaves the liver and helps maintain blood glucose levels
Pancreas secretes Glucagon➡️liver breaks down glycogen to glucose➡️glucose goes to blood➡️
Glucose is then used by the brain for energy needs ….burn down to CO2+ATP
**brain will have plenty of ATP
Pancreas secretes Glucagon➡️liver breaks down glycogen to glucose➡️glucose goes to blood➡️RBCs….
The red blood cells breakdown the glucose and turn it into lactate
Pancreas secretes Glucagon➡️liver breaks down glycogen to glucose➡️glucose goes to blood➡️RBCs turn glucose to lactate➡️
The lactate released from the red blood cells are sent back to the liver where it is converted from lactate to glucose
Pancreas secretes Glucagon➡️liver breaks down glycogen to glucose➡️glucose goes to blood➡️RBCs turn glucose to lactate➡️ lactate sent to liver to be turned into glucose➡️
Glucose is released back to the blood
Between 12 to 24 hours after fast is started where does the blood glucose come from
The blood glucose is coming from protein is taken from the muscle so the muscle is atrophying
Amino acids are being sent from the muscle to
Amino acid sent from the muscle to the liver through the blood since they are water-soluble
Wednesday amino acids are taken to deliver what happens to them in the blood
That amino acids are deaminated into urea
Once the amino acids are converted into urea….
Urea - N+ will be carried away as waste and carbons made into glucose (gluconiagenesis)
Once the urea is broken down and carbons are then made into glucose….
Glucose leaves the liver and supplies the blood with the glucose it needs to support the brain and red blood cells
During the fasting state we use that coming from
Adipose tissue
Triglycerides are broken down from adipose tissue because
Because glucagon will simulate hormone sensitive lipase to break down the triglycerides into glycerol
Turning triglycerides into glycerol can be used to make
This makes glucose in the liver also known as gluconeogenesis
Fatty acid from triglycerides in the adipose tissue can be
Can be used as energy for muscles and liver
Protein in the muscles are being used to break down into
Amino acids also known as gluconeogenesis to make my glucose
This starvation state is where fatty acid’s from adipose tissue turn into
Keytone bodies which are highly acidic so they are less desirable but under starvation conditions very useful source of energy
Keytone bodies in the starvation state can be used by
Keytone bodies can be used by the brain as a source of energy even though the brain prefers glucose but it will use it under starvation condition
The glycerol that does come from the adipose tissue is used to
Glycerol that does come from adipose tissue is small but it is enough to make glucose that can be released to the blood but mainly used by red blood cells because they can only use glucose and no ketones
Red blood cells use
Glucose
During the starvation state the brain will use
Ketone bodies
During the starvation state what happens to glucose levels
Glucose drops but not dramatically because of gluconeogenesis, lactate, amino acids, glycerol ,and fat
What will happen to plasma levels after several days of starvation
Glucose levels will lower and the Keytone bodies will greatly increase to make up for the loss of glucose and the fatty acid levels will increase by utilizing fat storage
In the urea what happens when glucose is high
When glucose is high then the nitrogen output is low
In the urea after fasting 12 hours what will you see
Putting out more nitrogen due to the burning of protein
After starvation for three days what will happen to urea
Depending on fat solubility so decrease in protein degradation
What happens to urea after starvation for 5 to 6 weeks
Not much protein is left and dependent on fat and there’s a decrease in nitrogen
How many types of nitrogen waste are there
4
The types of nitrogen waste are
Ammonia- made in kidneys
***Urea- made in liver and filtered by kidneys(most N found)
Utica acid- from breakdown of purines and caffeine
Creatine- made in muscles(interesting form found in urine)
Ammonia in nitrogen waste
NH4 is about 3%
Urea in urine
6%
H2N-C-NH2
ll
I
Uric acid in urine
11% and not very water soluble
Benzene ring with 2N and 1=O with a Pentene ring with 2N and 1=O
Creatine in urine
Pentene ring with 3N , 1=O, 1=NH, 1-CH3 extending group
Creatine phosphate is found in
It is found in muscles and used as molecule to quickly replenish ATP
The nonenzymatic decomposition of creatine is simply eliminated as creatinine.
Creatine phosphate degradation
The degeneration of creatine phosphate into creatine creates a molecule that cannot be used by other pathways so it will be released and filtered by the kidneys
Between meals with little to no glucose is entering the blood from the intestines the major source of glucose will be from
Glycogen
Increase your urea output usually indicates an increased use of
Amino acids
The starvation state is the same as the fasting state but
Keytone bodies become main source of energy
During the fasting state amino acids are converted into which molecule
Glucose
Keytone bodies are made in which organ and from which precursor molecule
In the liver from fatty acid’s
During the fasting state what happens to insulin levels compared to the Fed state
Insulin levels drop
Doing the fasting state what is the primary fuel for the brain
Glucose
When amino acids are burned what waste product is excreted by the kidneys
Urea
3 types of ketone bodies
B- hydroxybutyrate
Acetoacetate
used by muscle & NS
Acetone
expired in breath and not metabolized
