Week 4- upper GI condition intro

Question 1

what are the problems that people have to do with upper GI conditions due to acid?

Answer 1

• Wrong location (refluxing on oesphagus)
• Over-production 
• Faults with protective
mechanisms
• Dyspepsia

Question 2

what is the treatment for upper GI conditions?

Answer 2

• Prevent acid from relocating
• Reduce acid production or
neutralise it
• Remove cause

Question 3

what is the epidemiology for upper Gi conditions?

Answer 3

• 20-40% of ppl

- a quarter will have some ulceration

Question 4

what is gastric cancer? ppl its more likely to be in?

Answer 4

• stomach cancer
• 54% of cases are preventable
• more common smoker and drinker
• less likely in vegetarians
• salt intake
• infections related

Question 5

what are some common upper GI conditions ?

Answer 5

• Gastro-oesophageal reflux disease (GORD) 10-20%
• Duodenal and stomach ulcer disease (PUD) 10-25%
• Gastritis 30%
• Functional dyspepsia 30%
• Oesophageal & gastric cancer 2%

Question 6

what type of cells secrete pepsinogen?

Answer 6

chief cells and mucus cells

Question 7

how does pepsinogen have activity?

Answer 7

• converts to pepsin and has to have acid conditions

- Hydrochloric acid from Parietal cells

Question 8

what are the different phases of gastric activity associated with eating?

Answer 8

• cephalic phase
• gastric phase
• intestinal phase
• hormonal
• these phases can overlap

Question 9

acid secretion via Parietal Cells controlled by nervous control is done by how?

Answer 9

cephalic phase - parasympathetic

• Thought, smell, taste or sight of food

Question 10

acid secretion via Parietal Cells controlled by local control is done by how?

Answer 10

gastric phase - parasympathetic

• Distension of stomach and chemical make up

Question 11

acid secretion via horomal controlled by local control is done by how?

Answer 11

intestinal phase
• Food in duodenum (chyme) causes secretion of
somatostatin which inhibits acid production

Question 12

what is the gastric physiology ?

Answer 12

• Secretion of H+ from the parietal cells into lumen through protn pump for HYDORGEN AND POTASSIUM,
-histamine, gastrin released from G cells when they detects amino acids and peptides & acetylcholine (ACh) secretion of acid stimulated by acetylcholine relased by vagal fibres
-Gastrin
• produced in response to vagal stimuli, rise in pH and ingested protein & calcium
• stimulates growth of gastric mucosa
• Within the parietal cell H+ is produced via the proton
pump, exchanges H+ with K+ in the gastric lumen

Question 13

how do all the cells affect parietal cells?

Answer 13

• Parietal cell produces acid & directly stimulated by
• Vagus nerve – Acetylcholine (M3
receptor)
• Due to thought, sight, taste or smell
• Gastrin (G receptor)
• Due to contents of stomach
• Histamine (H2
receptor)
• Stimulation of enterochromaffin-like (ECL) cells by Gastrin & Vagus nerve
• Somatostatin is a prostaglandin and will suppress acid production
• Negative feedback due to contents of duodenum