Introduction Pathophysiology Flashcards

1
Q

____ is the constant low level of contractions that maintain smooth muscle in the walls of the GI tract

A

Tone
aka bowel sounds

“like a rubber band”
Tone declines over time as you get older - bloating, distention after eating, etc

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2
Q

Tone is important in maintaining a _______ _______. on the contents of the GI tract as well as in preventing its walls from remaining permanently stretched following distention.

A

steady pressure

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3
Q

The 4 functions of elaborate mechanisms

A
  1. motility
  2. secretion
  3. digestion
  4. absorption
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4
Q

The accessory organs of the digestive system are:

A

salivary glands, pancreas, biliary system, liver, and gallbladder

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5
Q

The intestine is ______ feet

A

30

21 - SI
9 - LI

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6
Q

The GI tract includes these organs:

A

mouth, pharynx, esophagus, stomach, duodenum, jejunum, ileum, cecum, ascending, transverse, descending, and sigmoid colons, rectum, anus

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7
Q

The 3 types of motility are:

superimposed on this ongoing tone

A
  1. Peristalsis (propulsive movements) - PSNS
  2. Segmentation (mixing movements)
  3. Sphincters or valves (TONIC CONTRACTIONS)
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8
Q

Peristalsis _______ contents forward through the GI tract at varying speeds.

A

propels

Involuntary contractions of smooth muscle

like a tidal wave - move things from point to point
“catch a wave and push you back to the shoreline”
to move things through the 30 ft of intestine

Slower in SI than esophagus

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9
Q

Segmentation promotes _______ digestion of food.

A

mechanical

sloshes things side to side

Exposes intestinal contents to the absorbing surfaces of the GI tract creating larger chance of absorption to occur

Involuntary contractions of smooth muscle

mainly occurs in stomach and SI - not everywhere like peristalsis

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10
Q

When sphincters ______ they are open, when they _______ they are closed

A

relax

contract

involuntary contractions - neural control
reflexes

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11
Q

The ______ _________ _________ separates pharynx from the esophagus

A

Upper Esophageal Sphincter (UES)

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12
Q

The ______ _________ _________ separates the esophagus from the stomach

A

Lower Esophageal Sphincter (LES)

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13
Q

The _______ ________ separates the stomach from the duodenum

A

Pyloric Sphincter

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14
Q

The _______ ________ separates the ileum from the cecum

A

Ileocecal Sphincter

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15
Q

The ______ _________ _________ separates the LI from the anus internally.

A

Internal Anal Sphincter

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16
Q

The ______ _________ _________ separates the LI from the anus externally

A

External Anal Sphincter

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17
Q

The ______ of _______. regulates the movement of contents of common bile duct into the duodenum.

A

Sphincter of Oddi

Not a GI sphincter but leads into it and regulates the flow of bile and pancreatic juice into the duodenum

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18
Q

A prime source of pathology in the GI system is sourced to the ___________.

A

sphincters

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19
Q

The voluntary actions contained in the GI regarding motility are contained in the _____ and the ______ ______ _______.

A

throat

external anal sphincter (EAS)

chewing, swallowing, defecation

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20
Q

The secretion of the GI tract _____ and ______ fluid.

A

makes

secretes

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21
Q

Secretion in the GI tract involves the diverse processes by which water, electrolytes are exported out of the cells. It is remarkable for both its magnitude and diversity. In a typical day the human body makes approx. ____ L of secretions.

A

9

  1. 5 L saliva
  2. 5L gastric juice
  3. 5L bile
  4. 5L pancreatic juice
  5. 0L intestinal secretions (small & large)
  6. 0L mucus (throughout the entire GI tract)
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22
Q

Digestion occurs ______, _______, and ________.

A

physically, mechanically, and chemically

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23
Q

The main chemical reaction that happens in chemical digestion is ___________.

A

hydrolysis

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24
Q

_________ are imbedded in the wall of the SI in the brush border of the SI.

A

Enzymes

The brush border is made up of epithelial cells that make up the mucosal surface of the GI tract.

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25
Q

Digestion occurs mainly in the ______ and the ______ _______.

A

stomach

small intestine

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26
Q

May of the enzymes are secreted into the GI tract lumen from places like the _______ and _________.

A

stomach

pancreas

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27
Q

________ as it occurs in the GI tract solves 2 remarkable problems.

A

Absorption

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28
Q

From the daily input of 9L only _____ mL gets put in the stool daily with the rest recycled.

A

100

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29
Q

When contents escape from the GI tract lumen there will be symptoms that often indicate GI _________.

A

dysfunction

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30
Q

To absorb nutrients effectively w/ water the molecular mechanisms by which they are carried out by involve both _______ and ________ transport.

A

active

passive

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31
Q

In __________ gastric juice penetrates the gastric mucosal barrier, injuring the gastric wall with its acidic and enzymatic contents.

A

Peptic Ulcer Disease (PUD)

The wall can erode all the way through and things escape - bleeding ulcer, leaches out of stomach into abdominal cavity.

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32
Q

In ______ _________ pancreatic juices escape the pancreas and/or the duodenum. The pancreatic digestive enzymes in the juice can cause widespread destruction of pancreatic tissue and possible hemorrhage.

A

acute pancreatitis

The pathogenesis of acute pancreatitis usually involves active secretion of pancreatic juice while the main pancreatic duct is obstructed at its entrance into the duodenum. The build up of obstructed secretions greatly increases the pressure within the duct system, causing the ducts to rupture and the pancreatic juice to escape.

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33
Q

In the case of a _______ _________ the colon wall tears open, allowing intestinal bacteria (flora) to except into the abdominal and pelvic cavities causing peritonitis or even death.

A

ruptured appendix

tears away from the wall of the cecum - intestinal contents into abdominal cavity

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34
Q

The two surfaces of the GI tract wall are the _____ and ______ surfaces

A

mucosal and serosal

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35
Q

The 4 layers of the GI tract wall are the _______, _______, _______ _______, and the ________. The thickness of these layers depends on where its located.

A

Mucosa
Submucosa
Muscularis externa - thickest in stomach
Serosa

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36
Q

The _______ layer of the GI tract consists of epithelial cells, lamina propria, and muscularis mucosae. Some places are curved and some are flat. This is the most outward layer to the lumen.

A

mucosa

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37
Q

The _______ layer of the GI tract consists of collagen, elastin, glands, and blood vessels. The glands secrete mucus into the lumen. This is the the second layer from the lumen.

A

submucosa

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38
Q

The _______ ______ layer or the GI tract is a circular and longitudinal muscle that is responsible for peristalsis (longitudinal) and segmentation (circular)

A

muscularis externa

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39
Q

The ______ is a thin serous membrane of the GI tract like a thin layer of saran wrap.

A

serosa

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40
Q

The GI nervous system layers include the ______ _______ _________ or ________ _________ _______.

A

Enteric Nervous System
Intrinsic Nervous System

All of the nervous tissue contained in the wall of the GI tract - subdivided into different layers (submucosal plexus - Meissner’s, myenteric plexum (Auerbach’s))

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41
Q

Nerves that originate outside the GI tract and innervate the various GI organs, namely, nerve fibers from both branches of the ANS. This is part of the _________ __________ system.

A

Extrinsic Nervous

PSNS 
-Vagus Nerve innervate:
esophagus
stomach 
SI
ascending colon 

Vagus are mixed nerves - 75% afferent (sensory) 25% efferent (motor)*

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42
Q

The Pelvic Nerves (Pelvic Splancnic) innervate the lower GI tract and derive from spinal nerve pairs ____, _____, and ______.

A

S2, S3, S4

innervate transverse, descending, and sigmoid colons, anal canal.

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43
Q

The majority of the PSNS, post-ganglionic neurons servicing the GI system are __________.

A

cholinergic (acetylcholine)

some are peptidergic - release peptide neurotransmitters

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44
Q

The GI tract also receives SNS innervation. 3 sympathetic ganglia that serve the GI tract are:

A

celiac
superior mesenteric
inferior mesenteric

These post-ganglionic fibers are adrenergic. 50% afferent, 50% efferent

SNS Slowing down digestion, secretion, motility

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45
Q

ANS nerves influence GI tract motility and secretion either by:

modifying ongoing activity in the enteric nervous system
altering the level of GI ____ secretion
acting directly on smooth muscle and glands

A

hormone

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46
Q

The principal glands of salivation are the ______, ________, and _______ glands

A

Parotid (largest of these glands)
Submandibular, and
Sublingual

In addition there are many small buccal glands. The daily secretion of saliva normally ranges between 800-1500mL.

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47
Q

Salivary gland secretions aid in lubrication and digestion of food, and enhance _____, _______, and swallowing. It also dissolves and washes out food particles from between the teeth.

A

speech, taste

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48
Q

-
-

A

acinus (grape-like sac like alveoli in lungs) blind end a branching duct system. Have lots of ducts that drain them

intercalated duct - salivary duct

striated duct

**The acinus merges into intercalated which merges into striated ducts)

*The striated ducts merge into bigger ducts that will drain saliva into oral cavity.

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49
Q

The ________ is comprised of a central lumen surrounded by pyramidal shaped cells. Each acinus is surrounded by a layer of __________ cells, which are elongated or star-shaped non secreting cells with long branching processes.

A

acinus

myoepithelial

Myoepithelial cells are also present in the intercalated ducts. When stimulated by neural input, the myoepithelial cells contract to eject saliva into the mouth.

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50
Q

-
-

A

serous
mucous
mixed - both mucous and serous

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51
Q

Stenson’s duct drains the _______ gland.

A

parotid

Is located near the upper 2nd molar

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52
Q

Wharton’s duct drains the _______ gland.

A

submandibular

is located at the base of understructure of tongue

striated ducts merge into Wharton’s duct

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53
Q

Unlike the parotid and submandibular glands, the sublingual gland lacks a single _________ duct. It is drained by approximately 10 small ducts (the Ducts of Rivinus) which exit the superior aspect of the gland along the sublingual fold on the floor of the mouth.

A

dominant.

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54
Q

The % of ____ electrolytes and protein makes up saliva w/ 99.5% water.

A

0.5%

pH 6-7.5
<5.5 enamel erosion (bulemia)

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55
Q

_________ is a salivary enzyme that begins digestion of carbohydrates in the mouth.

A

salivary alpha amylase

amylase = carbs

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56
Q

________ is a salivary enzyme that begins digestion of lipids in the stomach.

A

lingual lipase

lipase = lipids

**doesn’t work in mouth, only in stomach where the pH in stomach is more acidic and needs this++

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57
Q

_____mix w/ water to become mucus which lubricates the food.

A

mucins

58
Q

Salivary a-amylase _______ internal a-1,4 linkages only. It does not cleave terminal a-1,4 linkages or a-1,6 linkages. Salivary a-amylase is of relative limited importance, it is inactivated by gastric acid.

A

hydrolyzes

59
Q

-
-

A

lysozyme
lactoferrin
IgA

60
Q

_____ attacks bacterial cell walls (in the mouth and eyes)

A

Lysozyme

61
Q

________ which chelates Fe, preventing the multiplication of organisms that require it for growth.

A

lactoferrin

62
Q

________ which is active against certain viruses and bacteria (in mouth and other places)

A

IgA

63
Q

Salivary secretion is under _____ _______. The continuous, spontaneous secretion of saliva, even in the absence of apparent stimuli.

A

neural control

64
Q

The _______ _______ describes when food is in the mouth and afferent neurons can signals to the medulla. Salivary nuclei in the medulla receive the information. Then efferent neurons of the PSNS carry information via the CN VII (facial) and CN IX (glossal) to the salivary glands. The salivary glands secrete large amounts of saliva (very copius).

A

salivation reflex

65
Q

The saliva is ______ poor. The basal secretion is important in keeping the mouth and pharynx moist at all times.

A

protein

66
Q

Both ______ and _______ stimulation increase salivary secretion. But the quantity, characteristics, and mechanisms are different.

A

SNS and PSNS

67
Q

PSNS stimulation, which exerts the dominant role in salivary secretion, produces a prompt and abundant flow of watery saliva that is rich in enzymes. _____ and other cholinergic blocking agents reduce salivary secretion.

A

Atropine.

68
Q

SNS stimulation produces a much smaller volume of thick saliva than PSNS that is rich in ________. Because SNS stimulation elicits a smaller volume of saliva, the mouth feels drier than usual during circumstances when SNS system is dominant such as stressful situations.

A

mucus

69
Q

________ an inability to make normal amounts of saliva. Lead to dental caries, increased risk of infection, cotton mouth. Most of the time side effect of meds. Also can be due to Sjogren’s syndrome, HIV/AIDS, DM (bad blood flow to saliva glands, neuropathy), Parkinson’s. Also injury to head/neck that damage the nerves that stimulate salivary glands, radiation therapy for CA.

A

Xerostomia

anti-cholinergic properties

70
Q

The ________ is a flattened muscular tube of 18-26 cm from the upper sphincter to the lower sphincter. Between swallows the _______ is collapsed but the lumen can distend to approx. 2cm in the anterior-posterior dimension and up to 3-4cm laterally to accommodate a swallowed bolus.

A

esophagus
esophagus

When nothing in it, looks flat

71
Q

Esophageal __________ is non-keratinized stratified squamous. Epithelial continuity is critical for normal function. A breach in the epithelium creates an ulcer.

A

epithelium

72
Q

Esophageal _____ includes scattered esophageal glands. Esophageal glands provide mucus for lubricating the passage of food down the esophagus, augmenting the role of salivary glands.

A

submucosa

73
Q

The esophagus has no true _____ outer layer

A

serosal

Believed because it would be hard for motility; however it is covered by a thin and poorly defined layer of CT

74
Q

In the esophagus, the _____ _____ _____ includes large venous spaces. Within the esophageal wall.

A

submucosal vascular plexus

75
Q

Collaterals of the ____ _____ ____ a branch of the portal vein, receive venous drainage from the mid and lower esophagus plus from the submucosal venous plexus.

A

left gastric vein

76
Q

Esophageal varices are when these veins start to swell up because there is a lot of blood in them. Cause the mucosal layer to start to bulge. The greatest risk for these is ______ ________, and increase in pressure in the portal vein usually due to cirrhosis. Such varices carry a substantial risk of rupture w/ fatal bleeding into the esophageal lumen.

A

portal hypertension

77
Q

In a cirrhotic patient w/ portal hypertension, scarring occurs in the liver and this can cause the esophageal veins to back up and create ______ in the esophagus which can indicate a high risk of bleeding.

A

varices

78
Q

Swallowing (Deglutition) consists of 3 phases:
1.
2.
3.

Swallowing is initiated by the voluntary action of collecting the oral contents on the tongue and propelling them backward to the pharynx (oral phase). This starts a wave of involuntary contraction in the pharyngeal muscles that pushes the material into the esophagus as the UES relaxes and opens.

A
  1. Oral or voluntary phase - UES contracted. Tongue pushing food back.
  2. Pharyngeal phase -UES relaxes and opens. PSNS.

Also, inhibition of respiration and stimulation of glottic closure are part of the reflex response. Also the material tilts the epiglottis backward and down over the closed glottis as further protection from food entering the respiratory airways. Pressure inside pharynx elevates and causes UES to relax, also because food butting up against it.

  1. Esophageal phase - UES contracted. Peristalsis takes over. Peristalsis occurs whether or not food is present although the presence of food will intensify this contraction.

UES - close to heart so called cardiac sphincter

79
Q

Esophageal disorders include testing ______.

A

motility.

80
Q

_______ when the LES fails to relax and there is a backlog, food can’t enter the stomach Esophagus will expand and aspiration risk when lying down.

A

achalasia

not common in humans - dogs

81
Q

Various agents have been shown to decrease ______ pressure, which in turn decreases its closing strength. This permits reflux of acidic gastric contents into the esophagus which is aka ___________.

A

GERD

82
Q

Delayed gastric emptying also may contribute to reflux by increasing gastric volume and pressure with the greater chance for reflux. This common condition causes ______ and ________ and can lead to ulceration and stricture of the esophagus due to scarring. Furthermore current research indicates that there may be a strong casual relationship between GERD and esophageal adenocarcinoma.

A

heartburn and esophagitis

83
Q

Agents that may diminish the closing strength of the LES include:

A
fatty foods
chocolate 
ethanol 
peppermint 
spicy foods
citrus fruits
smoking 
BCP's
84
Q

Complications can result from persistent reflux, producing a cycle of mucosal damage that causes edema and erosion of the luminal surface. These complications include strictures and a condition called _______ ______ .

A

Barrett’s esophagus

Strictures are caused by a combination of scar tissue, spasm, and edema. They produce narrowing of the esophagus and cause dysphagia when the lumen becomes sufficiently constricted. Patients w/ dysphagia usually complain of choking, coughing, or an abnormal sensation of food sticking in the back of the throat or upper chest when they swallow.

85
Q

If swallowing is painful it is referred to as __________.

A

odynophagia

86
Q

Barrett’s esophagus is at risk of squamous mucosa being replaced by columnar epithelium (metaplasia) which can then become__________.

A

cancerous

87
Q

The 3 main regions of the stomach are:
1.
2.
3.

A

fundus - top portion of the J
body - vertical portion of J
antrum - curve of J

88
Q

The 3 layers to the muscularis externa are:

A
  1. outermost longitudinal layer - muscle fibers run vertical
  2. middle circular layer - muscle fibers run horizontal
  3. innermost oblique layer - muscle fibers run diagonal (for added mechanical digestion)
89
Q

The stomach lining or mucosa usually is impermeable to the gastric juice it secretes, a property that allows the stomach to contain acid and enzymes w/o having its wall digested. Several factors contribute to the protection of the gastric mucosa w/ the most important being a layer of alkaline mucus called the ____ _____ ______.

A

gastric mucosal barrier

layer of mucus on this layer

needs a pH 7 at this barrier - the lumen of the stomach can be a 2

90
Q

__________ play an important role in protecting the stomach mucosa from injury by enhancing mucus production.

A

Prostaglandins

“enhance fog layer”

NSAIDs inhibit prostaglandin production

91
Q

______ _______ are deep channels which are lined w/ columns of specialized cells called gastric glands. The mucosal surface of the stomach is a simple columnar epithelium that is dotted w/ millions of these.

A

gastric pits

92
Q

The gastric pits are lined w/ cells that come together to form ______ _______. These are lined w/ a variety of cells including mucous neck cells, parietal cells, chief cells, and endocrine cells.

A

gastric glands

93
Q

_____ _____ ______ secrete alkaline mucus

A

Mucous neck cells

Mucus has a lot of bicarb - creates layer of fog at surface of stomach lining mucosa.

94
Q

_____ ______ secrete HCl & intrinsic factor (IF)

A

Parietal cells (oxyntic)

95
Q

____ _____ secrete pepsinogen & gastric lipase.

A

Chief cells (zymogenic)

enzyme cells

96
Q

_________ _______ some secrete gastrin (G cells); others secrete histamine (ECL cells), which is working like a hormone.

A

Endocrine cells (enteroendocrine cells)

97
Q

______ __________ _________ only live for 2 days and have high turnover rate.

A

Surface lining cells

98
Q

_________ ________ replace and become surface lining cells, like stem cells.

A

Regenerative cells

99
Q

Everything except the _______ are dumped into the gastric pit.

A

hormones - go into blood, will also act in a paracrine way in addition to endocrine.

100
Q

The cells of the gastric glands secrete about 2500 mL gastric juice daily. The _____ secreted by the parietal cells kills many ingested bacteria, aids protein digestion, provides the necessary pH for pepsin to start protein digestion, and stimulates the flow of bile and pancreatic juice.

A

HCl

101
Q

HCO3- and mucus, prostaglandins, mucosal blood flow, and growth factors are all ______ factors in the stomach.

A

protective

102
Q

H+ and pepsin, H. pylori, NSAIDs, stress, smoking, and alcohol are all _______ factors in the stomach.

A

damaging

103
Q

In the fundus you find predominantly _______ _______, while in the body you predominantly find ____ ______, and in the antrum you find the ____ _____ predominantly.

A

parietal cells
chief cells
g cells

104
Q

The stomach temporarily stores ingested liquids and solids until they are released into the SI (3-5L). It vigorously churns food into a creamy soupy paste called ______. It secretes gastric juice that is involved w/ chemical digestion. It secretes the hormones ______ and _______. The stomach has to empty slowly because duodenum cannot handle this stored volume.

A

chyme

gastrin and histamine

105
Q

This phase of secretion & motility regulation includes the vagus nerve weakly stimulating gastric juice secretion when food is being chewed in the mouth or with the sight, smell, or thought of food.

Vagus nerve stimulates gastrin secretion from the enteroendocrine cells of the gastric glands. Gastrin (works in paracrine fashion) further stimulates secretion of gastric juice and affecting chief cells.

A

Cephalic phase

106
Q

How do parietal cells make HCl?

A

Proton pump - found on surface of parietal cells is responsible for making HCl. Take CO2 and H2O and convert to H2CO3 and then -> H+ + HCO3-. This is also a reverse reaction.

The H+ is pumped via the proton pump (H+/K+) into the lumen along w/ Cl- and HCl is formed.

The HCO3- is pumped into the blood w/ Cl- coming into the cell (this is alkaline tide, when the blood becomes temporarily alkaline after eating) along w/ Na+/K+ pump

PPI disables this proton pump inhibitor so less acid is concentrated.

107
Q

This phase of secretion & motility regulation begins when food reaches the stomach. Distention of the stomach and protein digestion products (amino acids) stimulate gastrin secretion and hence more gastric juice secretion —- this represents + feedback loop. Keeps distending and making more juice over and over.

Vagus nerve also continues to stimulate gastrin release and gastric motility.
Mechanical digestion starts also. Elevated levels of gastrin stimulate the release of histamine, which in turn increases HCl secretion from parietal cells.

A

Gastric Phase

108
Q

________ is not originally active but when it mixes w/ HCl it converts it into pepsin and pepsin digests dietary protein. Pepsin can partially digest amino acids but there will still be peptide chains left over. Still needs to be broken down to all amino acids, which will happen in SI.

A

Pepsinogen

109
Q

This phase of secretion & motility regulation includes small amounts of acidic chyme entering the duodenum which stimulates the secretion of 3 hormones that inhibit gastric juice secretion known as CCK (cholecystokinin), secretin, and GIP (gastric inhibitory peptide)

A

Intestinal Phase

GIP also inhibits gastric motility

CCK, secretin, and GIP all made in duodenum but secreted into stomach - they work to get the stomach to slow down so it doesn’t drain too fast.

CCK, GIP also affect:
pancreas
biliary system

110
Q

_______ _______ Products of protein digestion and H+ in the duodenum inhibit vagus nerve activity. Fatty acidic chyme also stimulate the release of CCK, secretin, and GIP — all of which inhibit gastric motility and emptying (occurs during the intestinal phase)

A

Enterogastric reflex

111
Q

________ is the inflammation of the stomach lining

_____ ______ is transient; most commonly associated w/ local irritants such as bacterial endotoxins, alcohol, aspirin, and NSAIDs. Depending on the severity of the disorder the mucosal response may vary from moderate edema and hyperemia to hemorrhagic erosion of the of the gastric mucosa.

Syx. include anorexia, nausea, emesis, transient pain, and usually disappear once causative agent is removed.

A

Gastritis

Acute gastritis

112
Q

______ _______ is atrophy of the glandular epithelium of the stomach; MC form is H. pylori.

A

Chronic gastritis.

113
Q

__ _______ survives in the stomach because it produces the enzyme urease, which generates substances (namely NH3- ammonia) that neutralize the stomach acid and enable the bacteria to survive. It penetrates the gastric mucosa

A

H. pylori

Burrows into the gastric pits and into the submucosa and if it keeps going - it is a perforated wall - bleeding ulcer.

114
Q

Within weeks of infection w/ H. pylori many people will develop _________, however most individuals will never develop ulcers.

A

gastritis

115
Q

Other risks for PUD include NSAIDs, _____, and _______.

A

smoking & ethanol

116
Q

Survival is possible w/ the stomach completely removed. ________ and ______ _____ ______ are adequate for full digestion, but

  1. food must be eaten in very small amounts, very frequently
  2. vitamin B12 supplements (not making IF)
  3. care should be taken to eat properly cleaned food to avoid intestinal infections
A

Pancreatic and
small intestinal enzymes

This is regarding gastric bypass, partial removal of stomach

117
Q

_______ _______ is in charge of the production of insulin & glucagon; plasma glucose regulation.

A

Endocrine pancreas

118
Q

______ _______ is in charge of production of the pancreatic juice

A

Exocrine pancreas

119
Q

The pancreas is a also a source of HCO3- to neutralize gastric acid and a source of many digestive _______.

A

enzymes.

120
Q

HCO3- and digestive enzymes are secreted by the pancreas as pancreatic juice (pH 7.6-8.2). Pancreatic juice travels from the pancreas to the duodenum via the main _______ ________. About 1500 mL of pancreatic juice is secreted per day. Bile and intestinal juices are also neutral or alkaline, and these 3 secretions neutralize the gastric acid, raising the duodenal contents to 6.0-7.0.

A

pancreatic duct

121
Q

The enzymes included in the pancreatic juice are:

A

pancreatic amylase
pancreatic lipase
colipase (helper to lipase)

Proteases: inactive 
trysinogen
chymotrypsinogen
procarboxypeptidase (A/B)
proelastase
ribonuclease - RNA
deoxyribonuclease - DNA
122
Q

The head of the pancreas interfaces w/ the _________ close to the common bile duct. The main pancreatic duct merges w/ the common bile duct. The juice will mix w/ contents being dumped into the duodenum from the stomach.

A

duodenum

123
Q

_____ acinar cells are also grapelike sacs that surround the pancreatic islets that make the pancreatic juice.

A

Pancreatic

124
Q

The opening into the duodenum is called ___ of _____.

A

Papilla of Vater

125
Q

Sphincter of Ode regulates the flow of both ____ and _____ juice.

A

bile

pancreatic

126
Q

________ will convert trypsinogen into trypsin which will then turn around and activate chymotrypsinogen, protealase, procarboxypeptidase A, procarboxypeptidase B into chymotrypsin, elastase, carboxypeptidase A, carboxypeptidase B

A

Enterokinase (aka enteropeptidase

brush border enzyme

127
Q

________ deficiency can occur as a congenital abnormality, which leads to protein malnutrition.

A

Enterokinase

128
Q

Releasing _____ in its active form can lead to a chain reaction of producing several active enzymes capable of digesting the pancreas. So the pancreatic tissue contains trypsin inhibitors.

A

trypsin

129
Q

Secretion of pancreatic juice is primarily under _______ control.

A

hormonal

130
Q

_______ acts on the pancreas to cause copius secretion of a very alkaline pancreatic juice that is rich in HCO3- and low in enzymes

A

Secretin

131
Q

_____ stimulates production of pancreatic juice rich in enzymes and low in HCOS-

A

CCK

132
Q

Stimulation of the PSNS within the vagus nerves also cause secretion of a small amount of pancreatic juice rich in ______ but this influence is much less potent than CCK. There is some evidence for vagally-mediated conditioned reflex secretion of pancreatic juice in response to the sight or smell of food.

A

enzymes

133
Q

Acute _______ is a severe, life threatening disorder associated w/ the escape of activated pancreatic enzymes into the pancreas and surrounding tissues. Small amounts of pancreatic digestive enzymes normally leak into the circulation but in acute pancreatitis, the circulating levels of digestive enzymes rise markedly.

A

pancreatitis

134
Q

Measurement of the plasma pancreatic ______ or _______ is diagnostic problems associated with inflammation and necrosis of pancreatic acinar cells.

A

amylase or lipase

135
Q

In pancreatitis these enzymes cause ___ ____ or auto-digestion of the pancreas and produce fatty deposits in the abdominal cavity with hemorrhage from the necrotic vessels.

A

fat necrosis

136
Q

Although a number of factors are associated w/ the development of acute pancreatitis, most cases result from ________ or ________ abuse.

A

gallstones (stones in the common bile duct)

alcohol

137
Q

In the case of biliary tract obstruction due to gallstones, pancreatic duct obstruction or biliary reflux is believed to activate the enzymes in the pancreatic duct system. The precise mechanisms whereby alcohol exerts its action is largely unknown. Alcohol is known to be a potent stimulator of pancreatic secretions, and it is also known to cause contraction of the Sphincter of Oddi of the pancreatic duct.

A

Small stone, big problems
‘Worst case for pancreatitis, flow of juice blocked
Acinar ducts will be ruptured and other things too

Cause Oddi to clamp down and not let go

Also if the stone is lodged there, the bile can go into the pancreas and activates the proteases leading to the havoc

138
Q

_______ _______ also is associated w/ hyperlipidemia, hyperparathyroidism, infections (particularly viral), abdominal and surgical trauma, and drugs such as steroids and thiazide diuretics

A

Acute pancreatitis

139
Q

MC initial syx of pancreatitis is severe epigastric and abdominal pain that radiates to the ______. The pain is aggravated when the person is lying supine; is less severe when the person is sitting and leaning forward. Abdominal distention accompanies by _________ bowel sounds is common. An important disturbance related to acute pancreatitis is the loss of large volume of fluid into the abdominal cavity. Tachycardia, hypotension, cool and clammy skin, fever often evident. Signs of hypocalcemia may develop, probably as a result of the precipitation of serum Ca2+ in the areas of fat necrosis. Mild _______ may appear after the first 24 hours because of biliary obstruction.

A

back

hypoactive

jaundice

140
Q

_____ _______ can result when a gallstone blocks the opening to the pancreas. The stone can lodge into an opening in the intestine. A pancreatic duct shares this opening; when it is blocked, the pancreas becomes inflamed.

A

Gallstone pancreatitis