Metabolism- Feast vs Famine Flashcards
(18 cards)
Best means to store xs fuel?
TG
-Have 2x caloric density and are hydrophobic
Primary target organs for storage?
Liver
Muscle
Adipose tissue
Fed state vs fasted statee
Fed=high insulin, low glucagon
Fasted=low insulin, high glucagon
Describe liver in fed state
Glucose brought in and stored as glycogen
Glucose–>G6P–>TG
VLDLipoproteins used for FA transport
Increase of proteins
Describe muscle fed state
Glucose brought in and stored as glycogen
AA brought in and stored as protein
Describe adipose tissue fed state
Same as liver but LPLipoproteins used
Describe liver-fasted state
FA increase outside of cell and ketones increase outside of cell
AA converted to urea
Glycogen broken down to glucose and transported out of cell
Describe muscle fasted state
Glycogen broken down to provide E
Ketones broken down to provide E
Glucose does not enter
Adipose tissue fasted state
Decrease TG to convert to glycerol and FA
Increase in FA
No lipid transfer into cell
Overall fed state
Storage promoted in liver, adipose, muscle
- Glycogen in liver and muscle
- TG in adopose
Protein synthesis promoted in all 3 tissues
OVeral fasted state
Glycogen storage in liver and muscle depleted and muscle protein broken down
AA used for glucose synthesis and TG in adipose are broken down.
Plasma FA and ketone concentrations increase and blood glucose concentration is prevented from decreasing dramatically
Starvation primarily involves a depletion of
Tissue fat and protein
Depletion of protein phases
Rapid depletion-1st stage
Slowed depletion-2nd stage
Rapid depletion-3rd stage/death
Explain effect of starvation on food stores of body
1- Carbs gone first within 1st week of starvation
Fats constant slope decrease
Proteins decrease
2-Fats decreased dramatically and ketone bodies are utilized to save proteins from being depleted. There’s a leveling off of proteins being depleted thanks to ketones being used as E source. week 3-5
3-Ketones gone, fats gone, proteins are now completely depleted. Week 8-death.
Death normally ensues in starvation when…
Proteins of body have been depleted to 1/2 of normal lvl
Does glucose enter intestine for absorption in ruminants?
-How do they manage?
NO
Porprionate (VFA) important precursor to make glucose in gluconeogenesis
How do ruminants support their glucose needs?
Conserving glucose
Where are FA made in ruminants?
Adipose tissue
-Synethsized from acetate not glucose
