(38) - Gastric Motility Flashcards
(Gastric Anatomy)
1-5. name the five compartments
- cardia
- fundus
- body
- antrum
- pylorus
(note position of the angulus - it is an important landmark)
(Gastric physiology)
- a two compartment model
1. The proximal portion (cardia, fundus, 1st third of corpus) - wat kind of contraction?
2. distal stomach (last 2/3 of corpus, antrum, pylorus - what kinds of contractions?
3. pacemaker cells in pacemaker site are similar to what type of cells? What will happen if pacemaker is lost?
- slow sustained contractions (tonic contractions)
- peristaltic contractions (phasic contractions)
- stem cells (become smooth muscle like); lost peristaltic contractions
- Where do you see emergence of electrical activity?
- orad corpus
(Say which belong to what part of stomach for each)
List proximal first
- receptive relaxation, propulsion
- trituration, accommodation
- retropulsion, eructation
- solid emptying, liquid emptying
- receptive relaxation, propulsion (movement from proximal to distal)
- accommodation, trituration (grinding)
- eructation (belch), retropulsion (goes back)
- liquid emptying, solid emptying
(Accomadation - Proximal Stomach)
- what is it?
- Can the stomach increase in volume with minimal pressure increase?
- pressure developing in stomach as a result of volume changes - the PV relationship
(the more food an animal eats there will be a pressure that will develop)
- yes
stomach becomes too stiff
less accomodation
triggers central satiety response
(Eructation - Proximal Stomach)
PROXIMAL STOMACH IS SITE OF ERUCATION RESPONSE
dilation of stomach
fundic innervation
neroun emanating from fundus that has synapse on lower gastro-esophageal sphincter - neroun becomes activated with trivial distension of stoamch with gas - causes inhibition to lower gastroesophageal sphincter (keeps it open) - causes belching of gas
how to fix this?
decompression of the stomach - pass a tube to vent
(Regulation of Gastric Emptying)
1-5. What are the five factors affecting Gastric Emptying?
Matt Preheim pets small iguanas
- modifying factors
- physics of emptying
- post-prandial patterns
- small intestinal regulation
- interdigestive patterns
(Gastric Emptying: Physics)
dv/dt = (Ps-Pd)/Rp
- What does (dv/dt) equal?
- What does (Ps-Pd) equal?
- what kind of resistance?
- rate of empyting
- pressure difference (between stomach and duodenum)
- pyloric resistance
(Gastric Emptying: Post prandial patterns)
- rate of empyting depends on what?
2-4. put from fastest to slowest (plastic spheres, dextrose, liver)
- diet
- dextrose
- liver
- spheres
(in general carbs empty faster than protein)
(Gastric Empyting: Modifying Factors)
- what temp empty’s fastest?
- what pH empties fastest?
- liquid or solid empty faster?
- body temp
- 7.4
- liquid
(Gastric Emptying: S.I. Regulation)
1-4. Once material empty from stomach into duodenum - there are receptors that recognize what three things? what affect does this have?
- what is this repsonse called? why?
- tryptophan content
- osmolality
- acidity
- feedback inhibition of gastric emptying
- (intestinal) ileal brake; cause most of effect is in distal ileum
(their are also lipid receptors in jejunum and ileum as well)
(Gastric Emptying: Interdigestive Patterns)
(Migrating (fasting) Motility Complex)
(takes place after feeding period)
(gets rid of indigestible material present after fed phase)
- Regulated by what GI hormone? Released when? How often in dogs?
- Does cat have this? What are the consequence of this?
- Motilin; during passive phase; two hours
- no (rabbits too) - have migrating spike complex (?); hairballs, plant material
(REgulation of Gastric Smooth Muscle Contraction)
- GI tract has what order neuron?
- Regulation at GI smooth muscle is thin or thick filament based? what is the official name?
- will drugs that affect troponin affect GI smooth muscle?
- What is the major NT in GI smooth muscle?
- third order
- thick filament; myosin light chain phosphorylation
- no - they affect light chain
- ACh
(Clinical Signs of Gastric Disorders)
(say +, -, or sometimes)
- dysphagia
- regurgitation
- vomiting
- salivation
- gagging
(say abnormal or normal)
- drinking
- -
- -
- +
- +
- -
- normal