Week 3: Small intestine motility

Question 1

Main functions of the small intestine

Answer 1

Question 2

What are the different types of contraction patterns in the small intestine?

Answer 2

• Segmentation
• Peristalsis
• Migrating motor complexes

Question 3

Describe segmentation contraction pattern

Answer 3

• Major contractile activity of the small intestine
• mixing function

Question 4

Describe the peristalsis contraction pattern of the small intestine

Answer 4

generally short-range propulsion, 15-20/hr

Question 5

Describe the Migrating Motor Complexes contraction pattern of the small intestine

Answer 5

Clearance at regular intervals during fasting state

Question 6

What is the most common type of contraction pattern in the small intestine?

Answer 6

Segmentation

Question 7

Function of the segmentation contraction pattern in the small intestine

Answer 7

effectively mixes chyme with digestive secretions “chopping” chyme as much as 8-12 times/minute

Brings fresh chyme into contact with the mucosal surface

Question 8

Describe the physiology of the segmentation contraction pattern

Answer 8

Question 9

What is the function of the peristalsis contraction pattern of the small intestine

Answer 9

contributes to propagation along the small intestine

Question 10

Describe the physiology of the peristalsis contraction pattern of the small intestine

Answer 10

Question 11

Describe the Migrating motor complex

Answer 11

Question 12

How are the small intestine contractile patterns regulated?

Answer 12

Question 13

Describe pacemaker activity in the small intestine

Answer 13

• electrical slow waves driven by interstitial cells of Cajal -5 sec intervals
• neuronal and hormonal activity act on top of slow waves to determine contractility

Question 14

Electrical slow waves

Answer 14

Question 15

Electrical slow waves

Answer 15

Question 16

Electrical slow waves

Answer 16

Question 17

Electrical slow waves

Answer 17

Question 18

Describe the hormonal regulation of motility

Answer 18

Question 19

Describe releasers of Gastrointestinal hormones

Answer 19

Question 20

Describe the actions of GI hormones

Answer 20

Question 21

Actions of GI hormones

Answer 21

Question 22

Actions of GI hormones

Answer 22

Question 23

Question

Question 24

Question

Question 25

Describe GI hormone regulation of motility in response to a meal

Answer 25

Question 26

Describe GI hormonal regulation in the fasting state

Answer 26

Question 27

Describe the function of enteric neuronal reflexes

Answer 27

Question 28

Describe the physiology of parasympathetic enhancement

Answer 28

Question 29

Describe the physiology of parasympathetic enhancement of the vagus nerve

Answer 29

Question 30

Describe the physiology of parasympathetic enhancement of the enteric ganglion

Question 31

how does parasympathetic enhancement regulate motility reflexes?

Answer 31

Question 32

What neurotransmitter is used for parasympathetic enhancement

Answer 32

Question 33

Summary of parasympathetic enhancement

Answer 33

Question 34

Describe the origins of sympathetic inhibition of

Answer 34

Question 35

Describe the physiology of sympathetic inhibition of

Answer 35

Question 36

Prevertebral ganglia sympathetic inhibition

Answer 36

Question 37

Prevertebral ganglia sympathetic inhibition

Answer 37

Question 38

What is the neurotransmitter of sympathetic inhibition

Answer 38

Question 39

How does sympathetic inhibition affect GI motility

Answer 39

Question 40

sympathetic inhibition histology

Answer 40

Question 41

Primary targets of sympathetic inhibition

Answer 41

Question 42

Presynaptic adrenoreceptors sympathetic inhibition

Answer 42

Question 43

Presynaptic adrenoreceptors neurotransmitter

Answer 43

Question 44

Effect of presynaptic sympathetic inhibition

Answer 44

Question 45

Sympathetic inhibition

Answer 45

Question 46

Examples of abnormal small intestinal mobility

Answer 46

Question 47

Describe post-operative ileus

Answer 47

Question 48

Summary of small intestinal motility

Answer 48