Endocrine regulation of energy metabolism/stress

Question 1

three major tissues involved in interconversion of energy substrates

Answer 1

liver, muscle, adipose

Question 2

only ____ provides energy

Answer 2

CHO/fat

Question 3

only excess _____ stored, not _____

Answer 3

CHO/fat

protein not stored (amino acids are converted for energy/storage

Question 4

two alternate states of metabolism and their main energy source

Answer 4

absorptive state - ingested nutrients

post-absorptive state - stored nutrients

Question 5

the absorptive state:

• ____ is main source of energy
• _____ forms of nutrients are favored
• _____ nutrients are stored
• _____-sparing state

Answer 5

• ingested glucose
• storage forms
• excess
• PROTEIN***-sparing state

Question 6

post-absorptive state:

• _____ are catabolized
• _____=main source of energy
• minor sources (____, ____)
• ____ is enhanced
• _____-sparing state

Answer 6

• storage forms of nutrients
• stored glucose/fat
• glycerol, ketone bodies (from fatty acids)
• gluconeogenesis
• GLUCOSE**-sparing state (meaning glycogen breakdown in order to increase blood glucose levels)

Question 7

Major hormones of energy metabolism:

• ____ - hypoglycemic hormone of the ____ state
• ____ - hyperglycemic hormone of the ____ state; also assisted by ____, ____, and _____

Answer 7

• insulin absorptive
• glucagon post absorptive
• glucagon assisted by EPI, cortisol, and GH

Question 8

Insulin: transition to absorptive state:

• ____ levels during a fast = ____ effect on post-absorptive state (to avoid _____ caused by glucagon)
• Food = ____ in insulin - converts to ______ state
• Insulin lowers blood levels of ___, ____, and ____ by stimulating peripheral tissues, liver, and adipose tissue

Answer 8

• low = braking effect (avoids hyperglycemia)
• sharp rise = absorptive state
• glucose, amino acids, and fatty acids

Question 9

insulin regulated by multiple factors:

• ____ (major control)
• increased _____
• increased _____
• ____ intake
• _____ stimulation
• inhibited by ______

Answer 9

• increased blood glucose
• increased blood amino acids
• increased GI hormones (food intake)
• food intake
• parasympathetic stimulation (food intake)
• inhibited by sympathetic stimulation ( and EPI)

Question 10

factors that increase blood glucose:

_____ OR ___

Answer 10

• glucose absorption from GI tract

- hepatic glucose production (glycogenolysis or gluconeogenesis)

Question 11

factors that decrease blood glucose:

______ OR ______

Answer 11

• transport of glucose into cells (for energy production or energy storage (glycogen or triglycerides))
• urinary excretion of glucose (occurs abnormally only when blood glucose levels are super high)

Question 12

Diabetes Mellitus:

• loss of ____ = severe metabolic derangement
• excess _____ - hyperglycemia = ______ = _____
• excess _____ = hyperlipidemia= _____ = _____ + _____
• excess protein degradation = ______ = excess ______ + negative _______

Answer 12

• insulin
• glucose = polyuria = dehydration
• lipids = ketogenesis = ketonuria + metabolic acidosis
• protein degradation = aminoacidemia = excess gluconeogenesis + negative protein balance

Question 13

GLUCAGON: TRANSITION TO POST-ABSORPTIVE STATE

• fall in plasma glucose ( + rise in ______) = glucagon rise - converts to _____ state
• glucagon raised blood levels of ___ and ____
• stimulates ____/____/____ in liver; ___ in adipose tissue; ___ in liver

Answer 13

• (amino acids) = post-absorptive state
• glucose and fatty acids
• glycogenolysis/gluconeogenesis/lipolysis
• lipolysis
• ketogenesis

Question 14

EPINEPHRINE: SECONDARY POST-ABSORPTIVE STATE

• direct actions on ____ (causing ____), ____(causing ___), and ____/____(causing ____)
• indirect effects by inhibition of ____/stimulation of _____
• EPI raises ____ and ____ during fasting
• EPI secreted in response to ______ (stress), so important in __________

Answer 14

-adipose (lipolysis), liver (gluconeogenesis), liver/muscle (glycogenolysis)
-insulin or stimulation of glucagon
-glucose/fatty acids
-acute hypoglycemia
EMERGENCY ENERGY NEEDS (may cause rebound hypoglycemia)

Question 15

CORTISOL/GH: ADDITIONAL POST-ABSORPTIVE ACTIONS

• minor physiological effects – stimulate ____ and ___ to support glucagon/fasting state
• GH directly stimulates ___ and indirectly stimulates ______(antagonizes ____)
• GH secreted in _____ (stress/exercise)
• cortisol enhances ____ + ______ + _____ (and antagonizes _____) in fasting/stress

Answer 15

-lipolysis and gluconeogenesis
-lipolysis
gluconeogenesis (antagonizes insulin)
-hypoglycemia
-lipolysis, gluconeogenesis, and protein catabolism (and antagonizes insulin)

Question 16

Major hormonal responses to stress:

• ____
• ____
• ____
• ____
• ____

Answer 16

-increase EPI
-increase CRH/ACTH/Cortisol
-increase glucagon
-decrease insulin
-increase Renin/Agiotensin-aldosterone AND Vasopressin (ANG II system to conserve salt/water to expand plasma volume; help sustain BP)
(AngII and vasopressin cause arteriolar vasoconstriction)

Question 17

insulin effects ____, ____, ____, _____

glucagon and EPI effect ____ and ____

Answer 17

• blood glucose, blood fatty acids, blood amino acids, muscle protein
• blood glucose, blood fatty acids (no effect on amino acids and muscle protein)

Question 18

major stimuli for glucagon secretion: ___ and ____

Answer 18

low blood glucose OR high blood amino acids

Question 19

major stimuli for insulin release: ___ and ____

Answer 19

high blood glucose OR high blood amino acids

Question 20

major stimulus for EPI release:

Answer 20

sympathetic stimulation during stress and exercise

Question 21

_____ is primary regulator of absorptive and post absorptive cycles

Answer 21

insulin

Question 22

major stimulus for cortisol release:

Answer 22

stress

Question 23

major stimulus for GH release: ___, ____, ____, ___

Answer 23

deep sleep, stress, exercise, hypoglycemia

Question 24

cortisol is only hormone that stimulates ___ and ____ at the same time

Answer 24

glycogenesis in liver

gluconeogenesis in the liver

Question 25

overall actions of cortisol in stress response: 3 things

Answer 25

• breaks down fat
• breaks down protein
• expands carbohydrate stores(glycogenesis) AND increases availability of blood glucose (gluconeogenesis)

Question 26

why does exercise have a profound effect in diabetes mellitus patients?

Answer 26

because exercise or muscle contraction triggers insertion of GLUT-4 into the plasma membranes of exercising muscle cells in the absence of insulin.

Question 27

major target tissues of insulin

Answer 27

liver, adipose tissue, and skeletal muscle

Question 28

major target tissues of glucagon.

Answer 28

mainly the liver

Question 29

how does insulin deficiency impact fat, protein and carbohydrate metabolism?

Answer 29

• Fat metabolism- increases lipolysis, increases fatty acids in blood, increases release of ketone bodies
• Protein metabolism- increased protein catabolism and muscle wasting, increased amino acids in blood, amino acids are used in gluconeogenesis to increase blood glucose
• Carbohydrate metabolism- glycogenolysis and gluconeogenesis proceed unchecked, hyperglycemia occurs with decreased glucose uptake in peripheral tissues.