2. basics cont. and endocrine system Flashcards Preview

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Flashcards in 2. basics cont. and endocrine system Deck (22):
1

4 roles of hormones at the onset of exercise

1 - fuel mobalization (liver, adipose, muscle)
2 - delivery (cardiovascular)
3 - fuel utilization (skeletal muscle)
4 - maintenance of thermal/fluid regulation (cardiovascular, renal)

2

role of insulin

substrate mobilization

stimulates
- glucose uptake into muscle

inhibits
- lipolysis (liver and adipose)
- hepatic glucose production

3

what increases and decreases glucose release from liver

increase
- catecholamines
- glucagon
- cortisol

decrease
- insulin

4

catecholamines
- release
- stimulation
- amount ratio

norepinephrine (NE)
- released from sympathetic nervous system (SNS)

epinephrine (EPI)
- adrenal medulla
- released stim by NE

- NE 7-fold higher than EPI
- EPI mainly produces the effect
- exponential increase with exercise

5

catecholamines effect
- fuel mobilization

increase muscle glycogenolysis (glycogen breakdown)
- activates glycogen phosphorylase

induces GLUT4 translocation
- brings glucose into muscle

6

one of the few hormones that decreases with exercise

insulin
- anabolic
- exercise is catabolic

7

glucagon released from

pancreas

8

role of glucagon

stimulates
- hepatic glucose production (gluconeogenesis)
- adipose tissue lipolysis (less important)

*counter hormone to insulin
- increases in response to exercise

9

cortisol secreted from

adrenal cortex

10

growth hormone secreted from

anterior pituitary

11

role of cortisol and growth hormone
- response to exercise

increases with exercise
- possible role in stim lipolysis and hepatic glucose production
- importance not yet clear

12

regulator of cardiac output during exercise
- which systems

main
- neural

others
- receptors in joints and muscle (act as accelerators)
- hormonal slower and less important

13

catecholamines role during exercise
- delivery (cardiac output)

mostly NE
- increase HR
- increase stroke volume (increase force of myocardial contraction)
- vasoconstriction of non-muscle (skin, splanchnic bed, kidney) and non-working muscle
- diversion of cardiac output to where its needed

14

insulin role
- substrate delivery
- why still decrease during exercise

stimulates glut4 and fat transporter movement to the plasma membrane
- increase glucose and FFA uptake into muscle

activates pyruvate dehydrogenase (PDH)
- increase glucose oxidation

acts as vasodilator
- increase blood supply

decrease during exercise*
- only want nutrient uptake by working muscle, not all tissues

15

delivery of substrate calculation
- how insulin is effected

concentration x blood flow

insulin
- decreases concentration
- increases blood flow (vasodilation)
- less total insulin but more reaches working muscles for nutrient uptake

16

catecholamines
- maintenance: temp and fluid balance

- reduce blood flow to skin (impairs heat dissipation* --> gets overridden)
- stimulates sweat production
- stimulates renin production (decreases plasma volume, manages blood pressure)

17

renin secretion

kidney
- increase with exercise

18

aldosterone secretion

adrenal
- increase with exercise

19

antidiuretic hormone secretion

posterior pituitary
- increase with exercise

20

renin, aldosterone and antidiuretic hormone
- function during exercise

increase with exercise
- conserve sodium and water to maintain/blunt the decrease in plasma volume (catecholamines cause decrease)
- regulate blood pressure

21

role of hormones in exercise

minor effect muscle substrate utilization

HGP and adipose tissue lipolysis
- catecholamines, insulin, glucagon

*main effect "delivery" and "maintenance"
catecholamines
- direct away from non-working muscle
- increase cardiac output
- thermoregulation and fluid balance

22

myokine

a cytokine
- protein involved in cell-cell communication
- released from muscle

ex. interleukin (IL-6)
- released by contracting muscle