Term
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Definition
| Regurgitation (without nausea) |
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Term
a reflex hypersalivation induced by esophageal reflux
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Definition
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Term
| Another name for heartburn |
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Definition
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Term
- Abnormal reflux of gastric contents into the esophagus causing symptoms OR mucosal damage
- Heartburn that occurs 2 or more days per week
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Definition
Gastroesophageal Reflux Disease (GERD)
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Term
Gastroesophageal Reflux Disease (GERD, alt. reflux esophagitis) is due to a ______activity which allows the (re)entry of stomach contents into the esophagus. The result is damage of the esophageal epithelia by acid and pepsin.
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Definition
| compromised lower esophageal sphincter (LES) |
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Term
The caustic effects of stomach contents may be due to a number of constituents:
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Definition
- HCl - hydrochloric acid (!!!)
Pepsin
Bile acids
Pancreatic enzymes (proteases and lipases)
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Term
___is the movement of gastric contents from the stomach intothe esophagus
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Definition
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Term
Opening of the LES is mediated in response to ___ as well as ____.
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Definition
the ingestion of food (swallowing);
the release of pressure from the stomach (eructation)
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Term
LES tone is modulated by
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Definition
| the autonomous nervous system |
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Term
| Effects of gastrin and secretin on Lower esophageal sphincter |
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Definition
Gastrin = increase LES tone
Secretin = decrease LES tone |
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Term
Relaxation during swallowing also involves “non-adrenergic non-cholinergic” neurons (NANC neurons) including ____and ____ neurons .
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Definition
nitrergic neurons (releasing NO);
VIPergic
(releasing vasoactive intestinal peptide VIP)
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Term
3 factors that can increase LES pressure
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Definition
1. High protein meals
2. Prokinetic agents (ex. metoclopramide)
3. Adrenergic alpha-1 agonist |
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Term
| Treatment for 3 stages of GERD |
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Definition
stage 1 = life style mod
stage 2 = prokinetics (metoclopramide, tegaserod) or antacids (short duration, take Q2H)
stage 3 = acid blockers (H2RA or PPIs) |
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Term
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Definition
Inflammation of the lining of the stomach
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Term
| Main difference between type A and type B chronic gastritis |
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Definition
Type A = autoimmune destruction of acid-secreting mucosa of stomach (fundal or autoimmune gastritis)
Type B (antral gastritis) = caused by H. pylori; is the most common type of gastritis |
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Term
| Achlorhydria, hypergastrinemia and neuroendocrine hyperplasia and neoplasm can occur in this type of gastritis |
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Definition
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Term
| Why is vitamin B12 deficiency common in type A chronic gastritis |
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Definition
| due to loss of parietal cells = low acid production (achlorhydria) |
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Term
H.pylori releases an enzymatic
marker; what is it and what does it
do?
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Definition
| Urease --> converts urea to CO2 and NH3, which neutralizes the acidic environment, allowing the survival of the bacteria. |
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Term
Some strains of H. pylori produces ____ that causes the formation of cellular vacuole
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Definition
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Term
If H.pylori convert urea to NH3 and CO2 which neutralizes acid, how come it is linked to ulcers?
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Definition
| When the neutralized gastric juice enters the duodenum it causes gastrin production and continous acid stimulation by parietal cells. |
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Term
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Definition
13-C Urea breath test &
Biopsy and culturing |
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Term
H.pylori alters host inflammatory response and damages
epithelial cells directly by _____or indirectly by _____
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Definition
directly = cell mediated immune mechanisms
Indirectly = activated neutrophils or macrophages. |
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Term
Patient ingests 13C-labelled urea. When H. pylori is present
in stomach membranes,bacterial urease produces
13C-labelled _____which is exhaled and measured.
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Definition
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Term
Common factor in the causation of peptic ulcer is ____
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Definition
| acid-peptic digestion of the mucosa |
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Term
Mostly caused by the
proteolytic action of pepsin
in an acidic environment.
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Definition
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Term
| 4 factors that cause peptic ulcer |
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Definition
- acid-peptic digestion of mucosa - most common
- mucosal ischemia
- inflammatory process
- infection
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Term
| most common type of ulcer (stomach or duodenum)? |
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Definition
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Term
Drug treatment of ulcers focuses on the suppression of
_________.
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Definition
| gastric acid production in parietal cells |
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Term
| T/F: only 35% of ulcers heal spontenously |
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Definition
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Term
| Release of HCl is caused by a unique enzyme, the ______. |
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Definition
H, K-ATPase (“proton pump”)
It is composed of a catalytic a-subunit (1034 aminoacids) and a ß- subunit (291 amino acids) and is located in the vesicle membranes. The half-life for the protein is approximately two days.
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Term
| Name and give examples of the 2 GI barriers. Which is most important and why? |
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Definition
Intrinsic barrier: Epithelial cells lines the digestive tract as a barrier
Extrinsic barrier: Mucus, bicarbonate, hormones and cytokines
Extrinsic barrier are more important because they protect the intrinsic cells
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Term
Bicarbonate production by ____ neutralizing hydrochloric acid
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Definition
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Term
To produce sufficient amounts of mucus and alkaline fluid, the _____ in the GI epithelia must be intact
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Definition
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Term
_______are due to a continuous stimulation of the
sympathetic nervous system that reduces stomach and
intestinal secretions by vasoconstriction of local circulation.
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Definition
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Term
Secretion of acid by the parietal cell is inhibited
by the 2 factors
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Definition
- Prostaglandins (mainly PGE2) acting via PG receptors
- Somatostatin acting on SST receptors
Both factors have the same signalling pathway, i.e. their receptors are negatively coupled to adenylatecyclase. Somatostatin, in addition to its effect on parietal cells, also has a negative inhibitory effect on ECL cell histamine release
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Term
Somatostatin, in addition to its effect on parietal cells, also has a negative inhibitory effect on ________
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Definition
| ECL cell histamine release. |
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Term
•Stomach protection is mediated by prostaglandins formed by ____.
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Definition
COX-1
•Classic NSAIDs inhibit both COX-1 and COX-2. Most “profens” preferably inhibit COX-1, others such as diclofenac prefer COX2 > COX1.
Some newer drugs (“coxibs”) are selective for COX-2 (e.g., rofecoxib). |
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Term
| 4 functions of prostaglandin |
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Definition
- inhibit acid and pepsinogen secretion
- increase blood flow in the stomach wall
- stimulate bicarbonate
- increase mucus secretion.
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