Appetite Regulation

Question 1

Orexigen

Answer 1

Substance that increases food intake

Question 2

Anorexigen

Answer 2

Substance that inhibits food intake

Question 3

What cell types sense nutrients in the gut lumen

Answer 3

Enteroendocrine cells

Question 4

What structures do Enteroendocrine cells use to sense nutrients in the gut lumen

Answer 4

Microvilli

Question 5

What feature of Enteroendocrine cells allows them to communicate with neurones and blood vessels

Answer 5

Contain vesicles for hormone release

Question 6

What causes receptor activation on Enteroendocrine cells

Answer 6

Nutrients

Question 7

What do mediators released by enteroendocrine cells activate

Answer 7

Chemoreceptors on vagal afferents

Question 8

What type of receptors detect gastric distension

Answer 8

Stretch stimulated Mechanoreceptors

Question 9

Is response to stomach distension a long or short term form of appetite control

Answer 9

Short

Question 10

Which nucleus is involved in appetite regulation

Answer 10

Arcuate nucleus

Question 11

What tissue produces adipokines inc leptin

Answer 11

Adipose

Question 12

What is the pattern of leptin secretion

Answer 12

Diurnal

Question 13

Does leptin have long or short term effects on appetite

Answer 13

Long term

Question 14

What does leptin signal

Answer 14

Satiety

Question 15

Actions of leptin

Answer 15

Inhibits NPY/AgRP Neurones
Activates POMC/CART neurones

Question 16

Is leptin orexigenic or anorexigenic

Answer 16

Anorexigenic

Question 17

Why can leptin not be targeted for obesity treatment

Answer 17

Leptin usually already high in obese individuals

Question 18

When is cholecystokinin released

Answer 18

In response to fat and protein

Question 19

Where is cholecystokinin synthesised

Answer 19

Duodenum

Question 20

Is cholecystokinin orexogenic or anorexigenic

Answer 20

Anorexigenic

Question 21

Effects of cholecystokinin

Answer 21

Slows gastric emptying
Released bile
Releases pancreatic enzymes
Activate vagus nerve to cause satiety

Question 22

What is caused by too much cholecystokinin release

Answer 22

Nausea
Taste aversion

Question 23

Is PYY 3-36 anorexigenic or orexigenic

Answer 23

Anorexigenic

Question 24

When is PYY 3-36 released

Answer 24

In response to high fat or protein

Question 25

What cells release PYY 3-36

Answer 25

L cells in GI

Question 26

How does PYY 3-36 cause satiety

Answer 26

Inhibits NPY neurones Activates POMC neurones

Question 27

What is the action of PYY 3-36

Answer 27

Increases satiety Long term negative regulator of body weight

Question 28

What groups have low PYY 3-36

Answer 28

Overweight Overweight in past

Question 29

How does insulin cause satiety

Answer 29

Inhibits NPY/AgRP neurones Activates alpha MSH/CART

Question 30

What is the most powerful Incretin

Answer 30

Glucagon like peptide

Question 31

Incretin

Answer 31

Gut hormones that stimulates insulin release after eating

Question 32

What causes GLP 1 release

Answer 32

Food intake

Question 33

What group has decreased GLP 1 level

Answer 33

Obese

Question 34

What causes release of pancreatic polypeptide

Answer 34

Food intake proportional to calories

Question 35

Is pancreatic polypeptide orexigenic or anorexigenic

Answer 35

Anorexigenic

Question 36

Is oxontymodulin anorexigenic or orexigenic

Answer 36

Anorexigenic

Question 37

Actions of oxontymodulin

Answer 37

Decrease plasma Ghrelin level Increase energy expenditure

Question 38

What is the major peripheral orexigenic hormone

Answer 38

Ghrelin

Question 39

Where is Ghrelin synthesised

Answer 39

Stomach

Question 40

What inhibits Ghrelin

Answer 40

Food intake - proportional to calories

Question 41

Does Ghrelin have short or long term effects

Answer 41

Both

Question 42

Where is Ghrelin found

Answer 42

Circulation in plasma

Question 43

Where can Ghrelin act

Answer 43

Receptors in brainstem Receptors in Mesolithic dopaminergic system Vagus Directly on hypothalamus

Question 44

How are Ghrelin levels altered in obesity

Answer 44

Decreased

Question 45

Why can Ghrelin not be targeted in obesity treatment

Answer 45

Already low in obesity May affect growth regulation Prevent beneficial effects of Ghrelin on CV system and inflammation

Question 46

Orexigenic hormones

Answer 46

Ghrelin Neuro peptide Y Agouti related peptide Orexins Melanin concentrating hormones Galanin

Question 47

Anorexigenic hormones

Answer 47

Leptin Cholecystokinin Insulin Glucagon like peptide Peptide YY Oxyntomodulin Cocaine and amphetamine regulated transcript peptides Corticotropin releasing hormone Melanocyte stimulating hormone

Question 48

What does the hypothalamus influence to regulate metabolic rate

Answer 48

Pituitary function Feeding Stress response Water balance Sleep wake cycle Thermoregulation

Question 49

What are the neural pathways that control food intake

Answer 49

Central orexigenic pathway Central anorexigenic pathway

Question 50

Which neurones are involved in the central orexigenic pathway

Answer 50

AGRP/NPY neurones in arcuate nucleus of hypothalamus

Question 51

Which appetite regulating neural pathway are POMC/CART neurones involved in

Answer 51

Central anorexigenic pathway

Question 52

What hormone activates the central orexigenic pathway

Answer 52

Ghrelin

Question 53

How do insulin and leptin effect the central anorexigenic and orexigenic pathways

Answer 53

Inhibits central orexigenic pathway Activate central anorexigenic pathway

Question 54

How does malonyl CoA affect food intake

Answer 54

Incr malonyl CoA -> suppress food intake Decr malonyl CoA -> increase food intake

Question 55

What process is malonyl CoA the first step in

Answer 55

De novo fatty acid synthesis

Question 56

What determines malonyl CoA

Answer 56

AMP/ATP ratio

Question 57

Is serotonin anorexigenic or orexigenic

Answer 57

Anorexigenic

Question 58

How does serotonin cause effects on appetite

Answer 58

Stimulate POMC neurone activity Inhibit AgRP neurone activity

Question 59

How do antidepressants affect weight

Answer 59

Can cause loss or gain

Question 60

How do cannabinoids effect food intake

Answer 60

Increase

Question 61

2 Endogenous cannabinoids

Answer 61

Anandamide 2 arachadonylglycerol

Question 62

What appetite control based drugs are recommended by NICE for obesity treatment

Answer 62

None

Question 63

Current obesity treatments

Answer 63

Lifestyle/behaviour changes Fat absorption inhibition - orlistat Bariatric surgery