Control of food intake

Question 1

What are 2 factors that enable accommodation of stomach to occur?

Answer 1

VIP + NO

Question 2

What is factor secreted in emptying of stomach?

Answer 2

Ghrelin

Question 3

What is definition of hunger?

Answer 3

discomfort caused by lack of food and desire to eat -> strong physiological drive for food/sensation of emptiness in stomach

Question 4

What is definition of appetite?

Answer 4

psychological desire/ drive to satisfy body’s needs of food-> hunger stimulated response

Question 5

What is definition of satiety?

Answer 5

state of being full after eating food

Question 6

What is definition of aphagia?

Answer 6

inability/refusal to swallow

Question 7

What is definition of hyperphagia/ polyphagia?

Answer 7

abnormal desire for food

Question 8

What is hypothalamus role in control of food intake?

Answer 8

control centre for appetite + food intake. controls hunger and thirst

Question 9

What is role of pre-frontal cortex in control of food intake?

Answer 9

• food seeking behaviour. it determines our food eating behaviour
• integrates sensory info from inside and outside of body
  receives emotional + cognitive info from limbic system
  helps one make choices by translating all homeostatic + environmental info into adaptive behavioural response

Question 10

What is role of limbic system in control of food intake?

Answer 10

• is complex system of nerves + networks in brain. areas concerned with instinct + mood. may control emotions.
• satiation of feeding behaviour behaviour is associated with motor planning + execution

Question 11

What is lateral hypothalamus?

Answer 11

Hunger/thirst centre

Question 12

What is ventromedial nucleus?

Answer 12

Satiety centre

Question 13

What is function of dorsomedial nucleus?

Answer 13

Modulates energy intake (hunger centre)

Question 14

What is function of paraventricular nucleus?

Answer 14

Modulates feeding behaviour

Question 15

What is arcuate nucleus?

Answer 15

collections of neurons in hypothalamus -> neurones produce orexigenic signals

Question 16

What is suprachiasmatic nucleus?

Answer 16

is where human body clock is located

Question 17

Stimulation of ventromedial nucleus leads to…

Answer 17

aphagia

Question 18

Lesions of ventromedial nuclei leads to….

Answer 18

hyperphagia

Question 19

Stimulation of lateral hypothalamus lads to…

Answer 19

increased feeding

Question 20

Lesions of lateral hypothalamus leads to…

Answer 20

aphagia

Question 21

Where is switch?

Answer 21

in hypothalamus

Question 22

How does orexigenic neurotransmitters affect feeding behaviour?

Answer 22

it increases appetite

Question 23

How does anorexigenic neurotransmitters affect feeding behaviour?

Answer 23

it decreases appetite

Question 24

What is circadian rhythm?

how does it affect food intake?

Answer 24

• sleep wake cycle
• 24hr internal clock that cycles between sleepiness and alertness
• limits food intake to certain times in some people

Question 25

[blood glucose] stimulates what type of receptors in hypothalamus?

Answer 25

stimulates glucoreceptors

Question 26

a decrease in [blood glucose] leads to...

Answer 26

upregulation of hunger

Question 27

a increase in [blood glucose] leads to...

Answer 27

upregulation of satiety

Question 28

How does distension of full stomach affect appetite?

Answer 28

it inhibits appetite

Question 29

How does contraction of empty stomach affect appetite?

Answer 29

It stimulates appetite

Question 30

What triggers CCK release?

Answer 30

Fat/lipid ingestion

Question 31

Where is CCK found?

Answer 31

I cells in intestine/nerve endings

Question 32

How does CCK affect appetite?

Answer 32

reduces appetite inhibits further food intake is satiety factor

Question 33

What is effect of somatostatin on food intake?

Answer 33

inhibits further food intake | is satiety factor

Question 34

What is adiponectin?

Answer 34

is factor released by insulin | has an impact on how we handle insulin or allows our body to regulate little bit how we respond to insulin effects

Question 35

What are 2 effects of insulin of control of food intake?

Answer 35

has catabolic and anabolic effects catabolic effect- decrease food intake anabolic effect - increase food intake

Question 36

Give 2 examples of orexigenic factors?

Answer 36

NPY and AgRP

Question 37

How does glucagon secretion during feeding affect satiety + glucose release?

Answer 37

it promotes satiety + promotes glucose release

Question 38

What is effect of amylin on feeding?

Answer 38

stimulated at same time as insulin | it reduces feeding

Question 39

What type of agents are insulin, glucagon and amylin?

Answer 39

anorexigenic agents =reduce feeding

Question 40

What is leptin? what does it control?

Answer 40

leptin is secreted by white adipose tissue which is endocrine gland. more white fat, more leptin secreted controls fat stores by operating feedback mechanisms between adipose tissue + brain increase in adipose tissue size -> increases leptin secretion

Question 41

What is ghrelin?

Answer 41

Appetite inducing horome (orexin) -> stimulates hunger released by stomach particularly upper oart, pancreas, adrenals in response to nutritional status. D1 cell type releases ghrelin

Question 42

What is obestatin?

Answer 42

produced by epithelial cells of stomach encoded by ghrelin gene but opposes the effects of ghrelin on food intake-> suppresses food intake, antagonises ghrelin induced food intake + growth hormone secretion

Question 43

Acting on a1 receptor leads to ...... feeding

Answer 43

decreased feeding

Question 44

Acting on a2 receptor leads to .... feeding

Answer 44

increased feeding