(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
(Gastric disease cont)
- bolus formation (-, +, or normal)
- dropping food (+, -)
- food ejection (immediate or delayed)
- character (digested or undigested)
- odynophagia (difficult in swallowing) (absent, occasional, frequent)
- swallowing (single, multiple, single/multiple)
- assoc signs?
- normal
- -
- delayed
- digested
- absent
- single
- retch
(Delayed Gastric Emptying)
1-6. List the six things that cause delayed gastric emptying?
PI GAME
- post-gastric dilatation/volvulus
- infectious/inflammatory gastritis
- gastric erosion and ulcer
- autonomic neuropathy
- metabolic disorders (uremia, addison’s disease, diabetes mellitus)
- electrolyte disturbances (K+, Ca++, Mg++)
Why do we see delay in gastric empyting after an animal has been appropriately treated for its gastric dilatation globulus?
this curve bitch
think about this in general
differentaite between mechanical obstrucitno and physiological (neuromuscular for example)
do we want to give prokinetic agents if it is obstruction? no! it will just shove up against obstruction - want to rule this out before moving on
SOMETHING THAT IS ASOSMOTIC WILL speed up gastric emptying!!
