NEUR 0010 - Chapter 16

Question 1

What are the three components of the hypothalamic response to regulate homeostasis?

Answer 1

Humoral response, visceromotor response, and somatic motor response

Question 2

What is the humoral response of the hypothalamus to homeostasis?

Answer 2

Hypothalamic neurons stimulate or inhibit the release of pituitary hormones

Question 3

What is the visceromotor response of the hypothalamus to homeostasis?

Answer 3

Hypothalamic neurons adjust the balance of SANS and PANS

Question 4

What is the somatic response of the hypothalamus to homeostasis?

Answer 4

Hypothalamic neurons incite appropriate motor behavioral response

Question 5

How is energy stored in the prandial state?

Answer 5

Glycogen and triglycerides

Question 6

Where are glycogen and triglycerides stores?

Answer 6

Glycogen in the liver and skeletal muscle; triglycerides in adipose tissue

Question 7

What is anabolism?

Answer 7

The assembly of glycogen and triglycerides from simple precursors

Question 8

What is the postabsorptive state?

Answer 8

Stores glycogen and triglycerides are broken down to provide the body with continuous energy like glucose, fatty acids, ketones, etc.

Question 9

What is catabolism?

Answer 9

The process of breaking down complex molecules

Question 10

Where are the hypothalamic cells that detect a drop in leptin?

Answer 10

Periventricular hypothalamus

Question 11

Where are the neurons that incite feeding behavior?

Answer 11

Lateral hypothalamus

Question 12

What is leptin?

Answer 12

A protein released by adipocytes, coded by the ob gene; regulates body mass by acting directly on neurons of yhe hypothalamus that decrease appetite and increase energy expenditure

Question 13

What is lateral hypothalamic syndrome?

Answer 13

Causes lack of appetite; anorexia

Question 14

What is ventromedial hypothalamic syndrome?

Answer 14

Causes overappetite and overeating; obesity

Question 15

What parts of the hypothalamus are the hunger vs satiety centers?

Answer 15

Hunger center = lateral; Satiety center = ventromedial

Question 16

What is the arcuate nucleus?

Answer 16

In the hypothalamus: contains leptin receptors

Question 17

What two NTs characterize arcuate nucleus neurons?

Answer 17

Alpha MSH and CART

Question 18

What is the body’s response to high leptin?

Answer 18

Humoral response (increased TSH and ACTH secretion to raise metabolic rate); Visceromotor response (increases SANS tone to raise metabolic rate); Somatic motor response (decreases feeding behavior)

Question 19

What triggers the humoral response to high leptin?

Answer 19

Activation of the paraventricular nucleus: causes release of hypophysiotropic hormones that stimulate release of TSH and ACTH from the anterior pituitary

Question 20

What triggers the visceromotor response to high leptin?

Answer 20

Activation of the paraventricular nucleus: affects the SANS to the lower brain stem and spinal cord; AND arcuate nucleus direct path: alphaMSH and CART neurons project into intermediolateral gray matter of the spinal cord

Question 21

What triggers the somatic motor response to high leptin?

Answer 21

Feeding behavior inhibited via connections of acruate nucleus neurons with cells in the lateral hypothalamus

Question 22

What are two anorectic peptides?

Answer 22

alphaMSH and CART: mimic response to elevated leptin levels; diminish appetite

Question 23

Low leptin triggers release of what two molecules?

Answer 23

NPY and AgRP

Question 24

What are NPY and AgRP?

Answer 24

Peptides released by the arcuate nucleus; in response to low leptin, DECREASE the secretion of TSH and ACTH (lower metabolic rate) and activate PANS

Question 25

What are two orexigenic peptides?

Answer 25

NPY and AgRP

Question 26

What part of the hypothalamus is responsible for feeding behavior?

Answer 26

Lateral hypothalamic area

Question 27

What is MCH?

Answer 27

Peptide hormone in the lateral hypothalamic area cells; informs the cortex of leptin levels in the blood, and motivates the search for food

Question 28

What is orexin?

Answer 28

Peptide in the lateral hypothalamic area cells: rise in the brain when leptin blood levels falls

Question 29

What is the hypothalamic response to low leptin?

Answer 29

Release in NPY and AgRP in the arcuate nucleus, and MCH and orexin in the lateral hypothalamic area

Question 30

What are the three phases of short term feeding regulation?

Answer 30

Cephalic, gastric, and intestinal (substrate)

Question 31

What is the cephalic phase of short term feeding regulation?

Answer 31

Activation of SANS and PANS to prepare you for food; salivating, smelling, etc.

Question 32

What is the gastric phase of short term feeding regulation?

Answer 32

When your stomach fills with food

Question 33

What is the substrate phase of short term feeding regulation?

Answer 33

When your stomach is filled and the nutrients begin to get absorbed

Question 34

What is ghrelin?

Answer 34

A peptide that stimulates hunger when stomach is empty; activates NPY and AgRP cells of the arcuate nucleus

Question 35

What are three main satiety signals?

Answer 35

Gastric distension, CCK, and insulin

Question 36

What is gastric distension?

Answer 36

Stomach stretching, which sends feedback to brain via vagus nerve

Question 37

Where do the sensory axons of the vagus nerve enter the medulla?

Answer 37

Through the nucleus of the solitary tract

Question 38

What is CCK?

Answer 38

Peptide that inhibits meal frequency and size: present in some intestinal lining cells; released by fatty food ingestion especially; acts on vagal sensory axons synergistically with gastric distension

Question 39

What is required for glucose transport into cells?

Answer 39

Insulin

Question 40

Why is insulin required for both anabolism and catabolism?

Answer 40

Need it to transport glucose into the liver/skeletal muscle/adipocytes for storage, but also to be liberated from storage to be used as fuel

Question 41

How do levels of serotonin vary by food intake?

Answer 41

Low serotonin in the postabsorptive state; rising serotonin when anticipating food; spike during a meal, especially for carbs

Question 42

What senses hypertonicity of blood and stimulates thirst?

Answer 42

OVLT (vascular organ of the lamina terminalis) in the telencephalon, lacks the BBB

Question 43

What part of the hypothalamus detects cold/heat?

Answer 43

Anterior hypothalamus: causes TSH release/inhibition from anterior pituitary