Goal 9: Ketone Synthesis Flashcards
Where is TAG stored? When TAG is degenerated, it releases what?
- stored in adipose tissue
- free fatty acids are released into plasma
The presence of insulin during the regulation of lipases causes what type of Hormone Sensitive Lipase (HSL)? What does epinephrine and norepinephrine do to HSL?
- dephosphylates HLS with phosphatase to make it INACTIVE in the presence of insulin= stimulates TAG degradation
- norepinephrine and epinephrine ACTIVATES HLS= inhibits TAG degradation
What do fatty acids need to bind to to get carried to other tissues? Why?
- they bind to albumin
- fatty acids are usually insoluble, albumin allows enough solubility to get through most tissues that are hypophilic
During what conditions does net degradation of TAGs happen?
- when glucose supply is limited to other organs, body needs energy source from something
- happens under well fed conditions
What are the 3 ketone bodies?
Acetoacetate, beta hydroxybutyrate (3-hydroxybutyrate), acetone
Where does Ketogenesis happen? What’s a precursor for it? Where is the precursor derived from?
- Liver’s mitochondria
- Acetyl CoA
- beta oxidation of fatty acids
Why is TAG degradation increased in starvation and diabetes mellitus?
- in starvation, your cells are starving without glucose;
- in DM, insulin is usually the ones that take the glucose into the cells to nourish it. Without the insulin, the cells are starving since the glucose stays in the blood instead of the cells.
- therefore, TAG degradation is turned on more because it thinks the body has no nourishment
Which ketone body is the major one that’s circulating in the plasma?
Beta-hydroxybutryate
What are the main Ketone bodies are used to get energy?
Beta hydroxybutyrate and Acetoacetate
Where in the body does ketogenesis happen? Where does ketone utilization happen?
-both in mitochondria of extra hepatic tissues
What is the key enzyme needed in the utilization of ketone bodies?
-Thiophorase
What is Kussmal’s respiration? Why does this happen?
- heavy, almost abdominal breathing to expel more CO2 in order to achieve acid-base balance since the ketoacidosis makes the blood more acidic
- it’s a compensatory hyperventilation, breath smells fruity from acetone
Where are a lot of ketone bodies used? Where are they not used at all and why?
- brain
- not used in RBC since there’s no mitochondria; not used in liver either because the liver needs thiophorase (thiophorase won’t form without mitochondria)
Ketone bodies are great sources of energy for what tissues?
Caridad and skeletal
Insulin decreases TAG degradation. How did affect ketone body production?
-decreases the rate of ketone body production
