Screening method of peptic ulcer disease.pptx 1.Introduction 2.Causes 3.Symptoms 4.Classification of antiulcer drugs Screening model (A) In vitro model (B) In vivo model A. IN VITRO MODEL 1. H+/K+ ATPase inhibition assay 2. Tiotidine binding assay 3. Gastrin binding assay B. In Vivo model 1. Pylorus ligation in rats 2. NSAIDs induced gastric ulcer 3. Ethanol induced gastric ulcer in rats 4. Histamine induced gastric ulcer 5. Acetic acid induced gastric ulcer 6. Cysteamine induced duodenal ulcer

1. Screening method of
peptic ulcer disease
Prepared By – Undhad Tushar C.
Masters Of Pharmacy Sem – 1 (Pharmacology) R.K. University
Under The Guidance Of – Dr. Pravin R. Tirgar
Ph D, M. Pharm - Pharmacology,
Professor, School Of Pharmacy, RK University
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2. contents
1. Introduction
2. Causes
3. Symptoms
4. Classification of antiulcer drugs
5. Screening model
 (A) In vitro model
 (B) In vivo model
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3. 1.Introduction
 Gastric ulcers may located at
the stomach or duodenum.
 Stomach ulcers are called
peptic ulcers and intestine
ulcers are called duodenal
ulcers.
Stomach ulcer
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4. 1.Introduction
 Studies showed that gastric ulcer occurs
at least 10% of the world population.
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5. 1.Introduction
 Peptic ulcer caused by a lack of balance
between the gastric aggressive factors and
defensive factors.
Aggressive
Factors
Defensive
Factors
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6. 1.Introduction
Aggressive
Defensive
 Acid, Pepsin, Bile, Helicobacter pylori
 Oily, Spicy, Irregular diet
 NSAIDS & other drugs
 Smoking, Alcohol, Stress
 Prostaglandin secretion
 Bicarbonate secretion
 Mucus secretion, Blood flow
 Rapid mucus turnover
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7. 2. causes
 H. pylori infection,
 Consumption of
alcohol ,smoking
 chronic consumption
of NSAIDs
ex aspirin ibuprofen
 irregulated acid
secretion
 Oily, spicy, irregular
diet habit, Stress
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8. 3.symptoms
 Acidity, reduced
pain after food
 Gastric bleeding Or
blood vomit
 Burning sensation,
nausea, vomiting,
heart burn, weight
loss
 Loss of appetite
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9. 4.Classification of antiulcer drugs
Class of drugs Example of drugs
H2 receptor antagonist Cimetidine, ranitidine,
Proton pump inhibitor Omeprazole, pantoprazole,
rabeprazole
Anticholinergics Pirenzepine, telenzepine
Prostaglandin analogue Misoprostol
Antacids Sodium bicarbonate, MgOH
Ulcer protective Sucralfate, colloidal bismuth
Anti H.pylori Amoxicillin, clarithromycin,
Metronidazole
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10. 5.Screening model
A. IN VITRO MODEL
1. H+/K+ ATPase inhibition assay
2. Tiotidine binding assay
3. Gastrin binding assay
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11. 1. H+/K+ ATPase inhibition assay
 PRINCIPLE:
 It is the final step in the synthesis of acid of
the parietal cell.
 PROCEDURE:
 Homogenate 80 ng microsomal gastric
H+/K+ ATPase incubated with 100 ul
buffer, 1 mM ATP and test compound in
microtiter plate for 30 min at 37 c.
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12. 1. H+/K+ ATPase inhibition assay
 Reaction is stopped by adding malachite
green (colorimetric agent)
 After 10 sec, 15% of sodium citrate is
added for 45 min.
 Release of orthophosphate by ATP is
quantified by colorimeter.
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13. 1. H+/K+ ATPase inhibition assay
 Evaluation:
 Percentage inhibition of H+/K+ ATPase is
calculated.
 Lower the orthophosphate release, more
is the inhibition of H+/K+ ATPase by test
compound.
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14. B. In vivo model
1. Pylorus ligation in rats
2. NSAIDs induced gastric ulcer
3. Ethanol induced gastric ulcer in rats
4. Histamine induced gastric ulcer
5. Acetic acid induced gastric ulcer
6. Cysteamine induced duodenal ulcer
Tushar_Undhad (Screening method of peptic ulcer disease)
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15. B. In vivo model
7. Reserpine induced gastric ulcer
8. Serotonin induced gastric ulcer
9. Diethyl dithiocarbonate (DDC)
induced ulcer
10. Methylene blue induced ulcer
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16. 1. Pylorus ligation in rats
 PRINCIPLE:
 The Pylorus part of the stomach was ligated , it
causes ulcers in rats by stopping the passage of
gastric contents from stomach and accumulation
of acidic gastric juice in the stomach for longer
time.
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17. 1. Pylorus ligation in rats
 PROCEDURE:
 Wrister rats are used
for the experiment.
(150 to 180gm weight)
 Animals are fasted for
48 hours.
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18. 1. Pylorus ligation in rats
 Animals are anaesthetized and a 1 inch
midline abdominal incision.
 The pylorus is carefully lifted out and ligated
without damaging its blood supply.
 The stomach is now replaced and the
abdominal wall closed with sutures.
 The test compound is administered orally
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19. 1. Pylorus ligation in rats
 10-19 hours later, animals are sacrificed and
stomachs are dissected out.
 Contents of the stomach are drained into a
graduated centrifuge tube and their acidity
determined by titration with 0.1N NaOH.
 Stomach is opened and ulcer index is
calculated.
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20. 1. Pylorus ligation in rats
 EVALUATION
 Ulcer index = 10/X
 Where X = total mucosal area / total ulcer
area
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21. 2.NSAIDs induced gastric ulcer model
 PRINCIPLE:
 NSAIDs cause ulcers by inhibiting
prostaglandins synthesis by inhibiting
cyclooxygenase enzyme in COX pathway.
 Prostaglandins play a protective role via
stimulating the secretion of bicarbonates and
mucous, maintaining blood flow and
regulating mucous cell turn over and repair.
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22. 2.NSAIDs induced gastric ulcer model
 PROCEDURE:
 Animals are fasted for 24-36 hours.
 NSAID (aspirin or indomethacin) using
appropriate vehicle (water or 1%
carboxymethylcellulose) is orally administered.
 After 1 hour, animals are treated with test drug.
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23. 2.NSAIDs induced gastric ulcer model
 4 hours later, animals are sacrificed,
stomach is removed and ulcer is
measured.
 Dose of NSAIDs:
 Aspirin- 150mg/kg of body weight.
 Indomethacin- 40-100mg/kg of body
weight.
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24. 2.NSAIDs induced gastric ulcer model
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25. 3.ETHANOL INDUCED GASTRIC ULCER IN RATS
 PRINCIPLE:
 Ethanol, being a necrotizing agent.
 Damages the superficial epithelial layers & inhibits
the release of mucosal
prostaglandins.
 PROCEDURE:
 Wistar rats are using( weighing 150-200 grams).
 Fasted for 18 hours before experiment.
Tushar_Undhad (Screening method of peptic ulcer disease)
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26. 3.ETHANOL INDUCED GASTRIC ULCER IN RATS
 Rats are given test drugs or standard drug
orally.
 30 mins later 1 ml/200gm of 99.% alcohol
is administered orally.
 After 1 hour, Rats are sacrificed and
stomachs dissected out.
 ulcer index are calculated.
Tushar_Undhad (Screening method of peptic ulcer disease)
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27. 4.Histamine induced gastric ulcer model
 PRINCIPLE:
 Histamine released from mast cells and
binds with receptors present on the
surface of cells which leads to activation
of adenyl cyclase.
 This adenyl cylcase converts ATP into c-
AMP
. This conversion enhances secretion
of HCL.
Tushar_Undhad (Screening method of peptic ulcer disease)
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28. 4.Histamine induced gastric ulcer model
 PROCEDURE:
 Male guinea pigs are
used. (300-400g)
 Fasting 36-48 hours, 50
mg of histamine sulphate
is injected via
intraperitoneal route.
Tushar_Undhad (Screening method of peptic ulcer disease)
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29. 4.Histamine induced gastric ulcer model
 Test drugs are administered after 30-45
mins of histamine injection
 5 mg of Promethazine HCl is given before
and after histamine injection. And sacrifice
the animals after 4 hours.
 Calculate ulcer index
Tushar_Undhad (Screening method of peptic ulcer disease)
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30. 5.Reserpine induced gastric ulcer model
 PRINCIPLE:
 Reserpine acts on cholinergic system.
 Reserpine increases histamine secretion
by causing degranulation of gastric mast
cells.
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31. 5.Reserpine induced gastric ulcer model
 PROCEDURE:
 Dawley rats are used for
the experiment.
 Animals are fasted for 48
hours.
 Test drug is administered
intraperitonially.
Tushar_Undhad (Screening method of peptic ulcer disease)
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32. 5.Reserpine induced gastric ulcer model
 Half an hour later, reserpine dose of
15mg/kg is administered intraperitonially.
 4 hours later, animals are sacrificed,
stomach are removed and dissected.
 Ulcer index is calculated.
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33. 6.Serotonin induced gastric ulcer model
 PRINCIPLE:
 Serotonin acts as vasoconstrictor which
reduces gastric mucosal blood flow and
leads to acute mucosal injury.
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34. 6.Serotonin induced gastric ulcer model
 Procedure:
 Animals are fasted for 24 hours.
 Serotonin creatin sulfate (20-50mg/kg) is
administered subcutaneously.
 Animals are sacrificed after 6 hours,
stomach is dissected out and calculate
ulcer index.
Tushar_Undhad (Screening method of peptic ulcer disease)
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35. Reference
 Essentials Of Medical Pharmacology 8th Edition 2018 By KD Tripathi+Pharmacological
Classification Of Drugs 6th Edition 2019 By KD Tripathi.
 Lippincott's pharmacology
 https://www.slideshare.net/roohna/screening-of-anti-ulcer-drugs?qid=a46c902e-8115-
4b4c-bef1-9e9497ecbc78&v=&b=&from_search=5
 https://www.slideshare.net/DivyaKrishnan4/screening-of-anti-ulcer-drugs-dr-divya-
krishnan?qid=7958fe8f-423f-4c50-92bf-dfef43a76c00&v=&b=&from_search=3
 https://www.slideshare.net/PriyaShukla62/antiulcer-screening-models-122796823
 https://www.slideshare.net/ShriyanshSrivastav/preclinical-screening-of-antiulcer-
shriyansh-srivastav-department-of-pharmacology-mpharmacy?qid=7958fe8f-423f-4c50-
92bf-dfef43a76c00&v=&b=&from_search=9
 https://www.slideshare.net/SivaYarasi/screening-models-for-evaluation-of-anti-ulcer-
activity?qid=7958fe8f-423f-4c50-92bf-dfef43a76c00&v=&b=&from_search=12
 https://www.slideshare.net/Aravind2018/screening-methods-of-antiulcer-
agents?qid=a46c902e-8115-4b4c-bef1-9e9497ecbc78&v=&b=&from_search=7
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