INtegrated Metabolism Flashcards
RBC
Its fuel reserve?
GLUT?
- Define the major metabolic pathways of the major organs consistent with their function.
- List the possible metabolic fuels and energy reservoirs for the major organ
RBC= No fuel reserve– remember no mitochondria, so no TCA
RBC glucose through GLUT 1
Major pathways glucose– hexokinase– glucose 6P
Glucose 6P can enter the PPP patwhy or Lactate– Cori Cycle
Through 1-3 BPG it can make 23 BPG producing lesser ATP by its glycolysis
BRAIN
Its fuel reserve?
GLUT?
- Define the major metabolic pathways of the major organs consistent with their function.
- List the possible metabolic fuels and energy reservoirs for the major organ
Very little fuel reserve, so it always needs supply of glucose
- GLut 3 and Glut 1 for BBB
high respiratory metaboism (uses 20% of the O2)
At Glucose G-6P junctions can go to
- PPP to make NADPH
- Pyruvate– PDH–> Acteyl Coa— TCA
** ketone bodies can come from liver into acetyl CoA when glucose deprived**
Skeletal and Heart Muscle
Its fuel reserve?
GLUT?
- Define the major metabolic pathways of the major organs consistent with their function.
- List the possible metabolic fuels and energy reservoirs for the major organ
Reserve-
Skeletal muscle—phosphocreatin and 2% of glycogen storage and during excessive exerise can use its AA to pyruvate/AcCoA to enter TCA and Alanine goes to liver for production of glucose
Heart– very low storage of phosphocreatin and glycogen and prefers fatty acid as energy but when starving uses glucose from liver, ketone bodies from liver, and FA from adipose
uses glut- 4 which is insulin induced.
At Glucose 6-P can heart and skeelta …
- Go to glycogen storage
- Go to PPP and make NADPH
- Go to pyruvate and turn to lactate (when anerobic)
- Go to pyruvate then AcetylCoA then TCA
Adipose
Its fuel reserve?
GLUT?
- Define the major metabolic pathways of the major organs consistent with their function.
- List the possible metabolic fuels and energy reservoirs for the major organ
Storge- TAG storage is 65% of it’s weight can acounts for 3 months of energy supply
Uses GLut 4– insulin stimulated (like cardiac and skeletal)
Preferred energy– Uses glucose and makes AcCoA for FA synthesis and the NADPH from the PPP. Also takes up FA from the liver
When Starving– releases it’s FA to blood
At Glucose 6P can go to
- GLycogen
- PPP
- Pyruvate to Acetyl CoA to lipogensis and fat storage
What’s special about brown fat
A lot in babies. This causes protons to reenter the mitochondria so it makes heat instead of ATP.
Oxidizes FA to make heat
LIVER
Its fuel reserve?
GLUT?
- Define the major metabolic pathways of the major organs consistent with their function.
- List the possible metabolic fuels and energy reservoirs for the major organ
Reserve- glycogen and can run glucogenolysis frm lactate, AA or glycerol during fasting
Glut 2– glucose enters and leaves through this receptor
Glucose 6-P
- GLycogen
- PPP- to make NADPH
- Pyruvate to LActate (normal lactate is coming in from muscle and feeding in for gluconeogensis because liver isn’t normally without O2)
- Pyruvate to Acetyl COa to TCA
- Acetyl CoA to Fat (VLDL) sent to adipose
Effects of hormones
Covalent modication of enzymes
Induction-repression of enzymes synthesis
So systems not affected by hormones (RBC) can’t have this done by hormones.
Target tissues of 4 main hormones
Target tissues:
Insulin: liver, muscle, adipose tissue
Glucagon: liver, adipose tissue
Epinephrine: liver, muscle, adipose tissue
Glucocorticoids: liver, muscle, adipose tissue
Metabolic processes stimulated by insulin
Dephos- normally anablic
GLycogen
Glycolysis (which increase FA synthesis)
Lipogenissi
Cholesterol Syn
AA synthessi
Promotes TG storage in adipose
Promotes glucose uptake by adipose and msucle
Metabolic processes stimulated by glucagon
Gluconeogensis/inhibts gylysis
Glycolysis/inhibits glycogen storage
Lipolysis in adipose
Degradtion of AA
Inhibits FA synthesis
What does epi mostly effect
The msucles. Similiar to glucagon (but glucagon doesn’t affect hte muscles).
Promotes release of glucose from the liver
stimulates glycogenolysis and lipolysis
How to hormones in circulating blood regulate each other
Epi would be high under stress/bur/trauma/cold/low blood glucose and it would down ergulated insulin and upregulate glucagon
4 types of hypoglycemia
- Insulin induced- too much insulin administered so drives blood glucose down– give oral glucose or inject glucagon
- Postprandal- post meal insulin shoots up too high– eat smaller meals to prevent
- Fasting hypoglycemis– shouldn’t happening because our bodies should compensate when fasting but if B-cells have tumor and insulin is too high or if hepatocytes are necrotic. Also in G-6_phosphatase defieicny glycogen or gluconeogensis can’t supply glucose.
- Alcohol induced- ehtnaol breaks down by Alchol DH which makes an NADH. This NADH pushes intermediates of TCA to other intermedias like pyruvate to lactate instead of TCA and the cell is starving for energy.
What happens after a meal
Insulin is HIgh
Glucagon, Epi and Glucocorticods are low
We store– glycogenesis in liver and muscle, lipogensis in adipose, glycsolysis for FA syntehsis, PPP for FA synthesis, increase choelsterold and increase AA
Liver- glycolysis, glycogensis, lipogensis (for VLDL), PPP
Muscle- glycolysis, glycogensis
Adipose- Lipogensis (and storage_, glycoslysis, PPP
Between meals
Insuling- low
Glucagon, Epi- high
Liver- glycogenosis, glucogensis, Cori and Ala cycles
Adipose- NOTHING aren’t starving yet
Muscle- glycogenolysis, glycolysis, Ala cycle
main source is glycogen and gluconeogensis
