Endocrine Control of Metabolism (Pathophys) Flashcards
How long is free glucose available for
One hour
How long is free glycogen available
1/2 days available
What tissues can only use glucose as fuel
Nerves, RBC, WBC, Renal tubules
How much glucose per day do nerves need
150 gm
Main metabolic objectives during and right after meal
Fill glycogen stores
Don’t pee out glucose
Utilize carbs and fats for energy
Package the excess
Main metabolic objectives in between meals
Keep glucose constant for CNS
Keep some glycogen reserve
Burn fat for energy and utilize separable proteins
What will muscle tissue do in presence of increased FA concentration
Body will use that instead of glucose
What organ responds to liver better than any other tissue
Liver
Main goal of metabolism b/w meals
Keep glucose constant for CNS
Short acting hormones*
Insulin, Glucagon, Epi, Norepi
Long acting hormones*
GH, TH, Glucocorticoids
Glucose level during 5 days of fasting
Stays at levels needed to supply nervous tissue
Insulin levels during 5 days of fasting
Drops but never hits 0
Glucagon level during 5 days of fasting
50% increase after a couple days fasting
Cortisol level during 5 days of fasting
Follows normal morning secretions
T3 levels during 5 days of fasting
50% drop in t3 during 5 days of fasting
How much does insulin increase after a meal
5x
Major lipolytic hormones**, what to they stimulate?
Epi and Norepi
Stimulates hormone-sensitive lipase
Insulin action in muscle and adipose tissue
Stimulates glucose consumption
Insulin action in liver
Inhibits glucose production
Hormones that all act in manner opposite to insulin
Epi, Glucagon, Glucocorticoids all act together to increase blood sugar
Epi vs GH for lipolysis
Epi acts much quicker and is much more potent
How do glucorticoids promote gluconeogenesis in liver
By complimentary mechanisms: induces key gluconeogenic and amino acid metabolizing enzymes in the liver
Also increases hepatic response to glucagon
How do glucocorticoids increase blood glucose in peripheral tissue
Increase AA release from muscle*
Increased glycerol release from adipose tissue