Control Mechanisms in GI Physiology Flashcards

1
Q

Parasympathetic effect on digestion

A

increases digestion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Sympathetic effect on digestion

A

decreases digestion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

*** A 65-year-old woman presents to the University Hospital emergency room complaining of severe diffuse abdominal pain associated with vomiting and diarrhea. She denies any abdominal symptoms prior to this episode. Her temperature is 37.80 Celsius, BP is 178/90 mmHg, and irregular pulse rate 120/minute. Physical exam is significant for extreme diffuse tenderness with rebound and rigidity. Which of the following nerve fibers most probably carry the pain sensation from GIT to the CNS ?

A

Sympathetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Nerve fibers that carry pain

A

Sympathetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Nerve fibers that carry nausea, distension, and satiety

A

Parasympathetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Nerve fibers that stimulate intestinal motility and exocrine secretion

A

Parasympathetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Nerve fibers that inhibit intestinal motility

A

Sympathetic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the inhibitory neurotransmitters in ENS?

A

Sympathetic

Norepinephrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the excitatory neurotransmitters in ENS?

A

Parasympathetic

Ach

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Hirschsprung’s Disease

A
  • absence of the myenteric plexus

* distal colon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Paralytic Ileus

A

most common cause: abdominal surgery

features: nausea and vomiting, abdominal distension, and absent bowel sounds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Anticipatory responses

A

Cephalic Reflexes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Vagovagal reflexes
Pain reflexes
Defecation reflexes

A

Long Reflexes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Gastrocolic
Enterogastric
Colonoileal

A

Short Reflexes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Peristalsis
Mixing contractions
GI secretions

A

Local Reflexes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

*** What would be the response of parietal cells if anticholinergic such as atropine is given?

A

decrease in Ach, but NOT inhibition

17
Q

Gastrin

A

G cells

  • increases gastric H+ secretion
18
Q

Cholecystokinin (CCK)

A

I cells

  • increases pancreatic enzyme & bicarbonate secretion
    (deals with fatty acids)

increase contraction of gallbladder

relaxation of sphincter of Oddi

19
Q

Secretin

A

S cells

  • increases pancreatic bicarbonate & water secretion

increases biliary bicarbonate secretion

( low pH = high H+ )

20
Q

Somatostatin

A

(deals with SNS)

decreases secretion of other GI hormones

  • decreases gastric secretion
21
Q

Histamine

A

(deals with PNS)

  • increases gastric H+ secretion
22
Q

Serotonin

A

increases intestinal motility and secretion

23
Q

Carcinoid tumors

A

enterochromaffin cells (most commonly secrete serotonin)

most commonly in ileum

24
Q

Carcinoid syndrome

A

once the carcinoid tumor metastasizes to the liver

25
Q

Acrtylcholine (Ach)

A

cholinergic

increases GI motility
relaxes sphincters
* increases H+ secretions
* increases pancreatic enzyme secretion

26
Q

Norepinephrine

A

adrenergic

decreases GI motility
contracts sphincters
increases salivary secretions

27
Q

VIP

A

decreases GI motility

* increases pancreatic bicarbonate secretion

28
Q

Substance P

A
  • co-secreted with Ach

increases salivary secretions