Integrative Physiology (Nutting) Flashcards
What are the body’s objectives during absorption and storage?
- fill glycogen stores
- don’t spill too much glu in urine
- utilize ingested carbs/fat for energy
- package whatever carbs/fats you don’t need as TAG and whatever aa’s as protein
During absorption and storage, what major processes are going on involving carbs?
increased glu uptake/utilization
increased glycolysis
decreased gluconeogenesis
decreased glycogenolysis
= increased glycogen stores
During absorption and storage, what major processes are going on involving fats?
increased lipogenesis
decreased lipolysis
=increased fat stores
decreased ketogenesis
During absorption and storage, what major processes are going on involving proteins?
increased protein synth
decreased protein degradation
=increased protein stores
What are the body’s objectives post-absorption (between meals)?
- keep glu constant
- decrease glu utilization
- keep some quick glycogen reserves
- burn fats for energy
- utilize the protein you can afford to spare
During post-absorption, what major processes are going on involving carbs?
decreased glu uptake/utilization
decreased glycolysis
increased gluconeogenesis
slightly increased glycogenolysis
slightly decreased glycogenesis
= only small decreases in glycogen stores
During post-absorption, what major processes are going on involving fats?
decreased lipogenesis
increased lipolysis (forming FFA + glycerol)
=decreased fat stores
increased ketogenesis
During post-absorption, what major processes are going on involving proteins?
decreased protein synth
increased protein degradation
=decreased protein stores
**esp in muscle, lymphoid tissue
What are the short-acting hormones involved in metabolism?
insulin
epi
NE
glucagon
What are the long-acting hormones involved in metabolism?
GH
thyroid hormone
GC
sex steroids
What is the onset and duration of short-acting hormones involved in metabolism?
rapid onset, with a brief (~mins) duration
What is the onset and duration of long-acting hormones involved in metabolism?
delayed (min-hours) onset, with prolonged (hours-days) duration
What is the primary mechanism of short-acting hormones involved in metabolism?
increase or decrease enzyme or protein activity
What is the primary mechanism of long-acting hormones involved in metabolism?
increase or decrease amount of enzymes or other proteins
How do the following levels change during prolonged fasting (up to 5 days, not between handfuls of Cheerios)? Glu: Insulin: Glucagon: Cortisol: GH: T3:
Glu: maintains steady level
Insulin: decreases (most significantly post-abs)
Glucagon: increases (but then remains steady)
Cortisol: remains constant
GH: increases
T3: steadily decreases (to decrease metabolic rate)
What hormone levels remain constant between the fasting and feeding phases?
cortisol
GH
T3
How is glucagon affected by fasting? By feeding?
decreases during/after meal
may increase between meals
How are Epi/NE affected by fasting? By feeding?
decrease during/after meal
tend to increase between meals
How is insulin affected by fasting? By feeding?
increases during/after meal,
decreases between meals
Effects of cortisol during/after meal?
Effects of cortisol between meals?
slight decrease in glu uptake and utilization (glycostatic)
- -Permissive to gluconeogenesis + lipolysis
- -Mildly decrease glu uptake and utilization