GIT_2 Flashcards
From which spinal segments does the nerve supply to the abdominal muscle arise from?
T13 + L1-3
what is the difference between a ganglia and a plexus?
ganglia = PNS synpases (symp NS)
plexus = PNS nerve network associated with ganglia (parasymp NS usually)
Where do the maj and min splanchnic nerves (Symp NS) synpase and what do they supply??
caeliaco-mesenteric ganglia
travel along arteries to abdo organs
Where does the lumbar splanchnic nerves synpase?
CD mesenteric ganglion
travel in hypogastric nerve –> pelvic organs
Where does the vagus lose its effect on the GIT?
transverse colon
after that = pelvic nerve from S1-3
passes through pelvic plexus then follows arteries to desc colon etc
describe the route of the vagus from the brainstem
vago-symp trunk down the neck
L & R vagus in thorax
join D & V as passes through the oesophageal foramen
D –> visc surface of stomach etc; V –> parietal surface of stomach etc
–> caeliac branch –> caeliacomesenteric plexus then to rest of abdo organs
Name the 4 arteries which supply the abdominal wall
- Cr abdominal
- Deep external iliac
- Cr epigastric (+cr superficial)
- Cd epigastric (+Cd superficial)
Major branches off the aorta supply the abdominal organs. Name the main 3
- Caeliac
- Cr mesenteric
- Cd mesenteric
The caeliac gives rise the arteries which supply the liver, stomach, cranial duodenum and what else?
spleen & oesphagus!
describe the branches of the caeliac
- hepatic a
- cyctic a
- R gastric a
- gastro-duodenal a
- L gastric a
- oesophageal a
- Splenic a
- short gastric aa
- pancreatic aa
- L gastro-epiploic a
describe the arterial supply to the stomach (5a)
R gastric –> R lesser curv
L gastric –> L lesser curv
R gastro-epiploic –> R greater curv
gastric aa –> greater curv
L gastro-epiploic –> L greater curv
Describe the arterial supplies to the R lobe of the pancreas
caeliac = Cr pancreatico-duodenal (cr lobe)
cr mesenteric = Cd pancreatico-duodenal
what are the major branches of the cr mesenteric a?
ileo-colic a
cd pancreatico-duodenal
jejunal aa
the ileo-colic a has 5 main branches, name them
- mid colic a
- r colic a
- colic branch
- caecal branch
- mesenteric ileal
which branch of the ileo-colic supplies the a) asc colon and b) desc colon?
a) mid colic
b) colic branch
what does the cd mesenteric supply and with what branches
L colic a –> L colic flex and desc colon
cranial rectal a –> rectum (cranial)
The kidneys, ovaries and testicles recieve arterial supply directly from the aorta via different branches. Name them
L&R renal aa
L&R ovarian aa
L&R testicular aa
most of the blood supply to the GI organs will anastomose. why does this happen?
to prevent ischemia in the event of an arterial blockage eg thrombus or embolism
Do all the abdominal organs drain via the hepatic portal system ?
NO. only the GI ones.
(Unless you are a reptile/bird/fish with a renal portal system as well)
fat (chylomicrons) do not drain via this either
what organs drain directly into the Cd VC?
- Liver (ha ha…..)
- kidneys
- ovaries
- testicles
- NOT L test vein as it drains into the renal v..
Mostly there are corresponding veins to arteries. Name the exceptiions
No celiac vein (not needed as hepatic v is there already!)
L gastric drains into the splenic v NOT hepatic portal (long winded route..)
L testicular v drains into the L renal v NOT Cd VC?! werid..
In the simple stomach the greater and lesser curv of stomach are supplied by L&Rgastro-epipl and L&R gastric. In the ruminant stomach what is the equivalent
ruminoreticulum & g curv of abom = L&R gastro-epip
omasum & l curv of abom = L&R gastric
The caecal supply in the ruminant is the same as the dog (caecal br of ileo-colic and anti-mesenteric ileal). What is it in the horse and pig?
medial caecal
lateral caecal
NO antimesenteric!
what is the PX asc colon referred to in the horse, cow and pig? What supplies it (arterially)
horse = ventral colon
pig/cow = centripetal coils
arterial supply = colic branch of ileo-colic
the distal asc colon is the dorsal colon in horses and the _________ in pigs/cows. What is its arterial supply?
centrifugal coiils
R colic supply
Describe the main differences between the omentum in the horse and dog
Doesnt cover intestines
epiploic foramen –> colic
poor development = susceptible to peritonitis
How do you locate the epiploic foramen?
in between the hepatic portal triad and the Cd VC
Describe the attachment of the omentum in the ruminant
superficial layer –> LHS rumen & RHS desc duodenum
deep layer –> RHS rumen & RHS desc duodenum
in ruminants there is an additional space (to the omental bursa) what is it called and where is it?
supraomental recess
inbw colon and deep layer
how does the equine an druminant liver sit in situ?
horse - oblique LHS; rounded border = left and dorsal
ruminant - 90 degrees; Rounded border = left (R lobe dorsal; L lobe ventral). RHS!
What animal does not have a renal impression on the caudate lobe? (RHS)
pig - liver doesnt comin into contact with kidney
Name the 4 basic lobes of the liver
- left
- caudate
- right
- quadrate
The caudate lobe has a papillary process, in which animal is this almost larger than the caudate lobe itself?
Sheep
what 2 features is the horse missing from its liver?
gall bladder
papillary process of caudate lobe
L & R lobes are subdivided in the dog, what other animals have these subdivisions and what are they calle?
pig and cat
med and lat
describe the shape of the spleen in:
horse
ox
sheep
pig
dog
horse - comma
ox - tongue
sheep - oval
pig - long, v red!
dog - hockey stick
Dogs and horses have both an accessory and pancreatic duct. Cows/Pigs only have an accessory duct, what about sheep?
Just pancreatic
When the pancreas surround the portal vein, what is it called? (horses and pigs only)
annulus pancreatis
what is a distinguishing feature of the pig stomach
large cardiac region
the horse stomach contains an enlargement of the fundus called _______
also a structure called the margo plicatus - what is this?
saccus caecus
margo plicatus = separates glandular from nonglandulat sides of the stomach.. fave spot for gastrophilis larva
What do both pigs and ruminants have due to both having a poor pyloric sphincter
torus pyloricus
what parts of the ruminant stomach are accessible on the LHS
D
V
Cd-V
(some) abomasum - not much hence LDAs
Cd-D
reticulum
both pigs and ruminants colon are centrifugal and centripetal. however the shape is different - describe
pigs = spiral
rumin = coiled
in pigs the ________ coils are haustrated with taenial bands
centripetal
describe the pattern of taenial bannds in the horse LI
Caecum = 4
RVC = 4
LVC = 4
LDC = 1
RDC = 3
TC = 2
SC = 2
what can be found on the LHS of a pig?
caecum and colon
what can be found on the RHS of a horse
caecum
R colon
liver (most)
what can you palpate in the different quadrants of the horse
LD = jej/small colon
LV = pelvic flex
RD = base of caecum
RV = body of caecum
what are the different layers of the GIT?
mucosa
submucosa
muscularis
serosa
what is located in the mucosa layer>?
lamina epithelialis
propria
muscularis
where are the large blood vessels nerves and glands found?
submucosa
is the circular muscle layer inner or outer?
inner
what is serosa?
mesothelium (w mvilli) and CT (with nerves, vessels and fat)
what is the epithelium in the oesophagus?
strat sq
is the muscle in the oesophagus smooth or skeletal/?
skeletal in dogs and cows; partially skeletal in cats and horses
in the mucosal layer, where would you find the glands?
laminal epithelialis. in the stomach = mucus, acid and pepsin glands
what and where is the stratum compactum>
mucosa is thickened to protect
how can you recognise chief cells
zymogen granules (pepsinogen)
what do parietal cells secrete?
HCl
what epithelium is in the SI/
columnar epi w/ mvilli
what cells can be found in the crypts of SI?
paneth = basal nuc. secrete lysozyme
what varies in the submucosa between species, in the SI?
type of glands present
mucus - dogs
mixed - cats
serous - horses
what are these submucosal glands called in the duodenum of dogs?
Brunner glands
how can you tell the difference (histologically ) bw duodenum and ileum?
ileum villi = club shaped
inc goblet cells
inc lymph nodules
what are some chacterisitc features of the colon?
inc goblet
no villi, still has crypts
lots of lymph tissue
where do you find kupffer cells?
mphages in sinusoids of the liver
in the different areas of the GIT the mucosa changed mostly, what specific area of the ruminant stomach will change in each part
lamina muscularis
what is the epi layer of the ruminant stomach
keratinised strat squamous
are the reticulum, rumen and omasum glandular?
no, derived from oesophageal regions
what is characteristic of reticulum
honeycomb
what is unsual about the honey comb structure
isolated smooth muscle, they contract to keep heavy difficult to ferment food
what epithelium is found in the rumen?
cornified strat sq
what is unusal about the lamina muscularis mucosae in rumen
none
what is unusual about the histology of the omasum?
sheets with papaillae with smooth muscle following it
the muscularis layer interdigitates with this too
what is in the rumen to increase VFA absorption?
papilla
