Stomach Flashcards
For the greater and lesser curvatures, describe the curvature (convex, concave), direction of curvature and length (in relation to other curvature)
Greater curvature: is convex, curves to the left, is longer than the lesser curvature
Lesser curvature: is concave, curves to the right, shorter than greater curvature
Describe the 2 surfaces of the stomach and what they face
Parietal surface: cranial facing, faces liver and diaphragm
Visceral surface: caudal facing, faces abdominal viscera (mainly intestines and spleen)
The _______ sphincter is connected to the oesophagus and the _______ sphincter is connected to the duodenum
Cardiac sphincter, pyloric sphincter
Name the 3 main connective tissues (peritoneum) from the stomach and what they cover/ connected to
Hepatogastric ligament: connects the liver to stomach
Greater omentum: a loose fold along the greater curvature
Lesser omentum: loose fold along the lesser curvature, which extends to the liver
Name the 4 ‘sections’ of the stomach and what theyre connected to, also include which is the largest portion.
Cardiac: where the oesophagus connects to the stomach
Fundus: between the body and cardiac, bulges cranially
Body: major part of the stomach
Pyloric antrum: leads to the exit, into the duodenum
Name the 4 layers in a cross section of the digestive tube.
Mucosa, submucosa, muscularis externa (tunica muscularis), serosa
What are the 2 types of mucosa, what epithelium covers it and what colour are they?
Non-glandular: stratified squamous epithelium. Whitish-colour
Glandular: simple columnar epithelium (secretory), reddish-yellow colour
Describe the glands located in the pyloric region and what they secrete
Short, branching, coiling glands opening into deep gastric pits.
Produce mucus/ gastrin
Describe the glands located in the cardiac region and what they secrete
Simple, branched, tubular glands producing mucus
Describe the glands located in the function region and what they secrete. What is another name for these glands
‘Proper gastric glands’
Tubular glands producing HCl/ enzymes (secretion specific to the stomach)
What type of tissue is commonly found in the cardiac region of the stomach (within the mucosa)
diffuse and nobular lymphoid tissue
What is the protective function of mucus in the stomach
Protects the stomach epithelia from being damaged by HCl and pepsin
What is the lamina propria
The loose connective tissue between the gastric pits/ gastric glands
What cells are located within the lamina propria
Lymphocytes, eosinophils, plasma cells, mast cells
What 3 types of glands are located in the gastric pits OF FUNDIC GLANDS? (provide both names if more than one name)
Mucous neck cells, chief cells (peptic cells), parietal cells
Describe the mucous neck cell epithelia (including type, nucleus, cytoplasm stain)
Epithelia: cuboidal/ low columnar
Nucleus: flat, basal nucleus
Cytoplasm: slightly basophilic (more basic)
Stain purple with PAS stain due to granules
Where are mucous neck, chief and parietal cells found?
Mucous neck: found only in the neck of the gastric pit
Chief: mainly in the lower 1/3 of the base/ fundus gland
Parietal: throughout the fundic glands
What do mucous neck cells secrete?
Mucus, for protection
What do chief/ peptic cells secrete, and what happens to these secretions
Pepsinogen/ prorenin which are converted into active enzymes in the gastric lumen
What do parietal cells secrete?
HCl
Describe the parietal cell epithelia (including type, nucleus, cytoplasm stain)
Pyramidal shape with a central nucleus
Strongly eosinophilic (pink stain)
Describe the chief cell epithelia (including type, nucleus, cytoplasm stain)
Cuboidal/ pyramidal in shape with a basal nucleus
Basophilic (basic - blue stain)
Describe the structure of cardiac glands, what type of secretion they produce.
Simple, branched tubular glands
Mucus secreting cells
Describe the depth of the gastric pits/ glands of the pyloric glands in relation to glands in the rest of the stomach.
The gastric pits are deeper in the pyloric gland region than in other areas, but the pyloric glands are relatively short, but highly branched
What additional cells are located within the pyloric region and what do they do?
Enteroendocrine cells (G-cells) which secrete hormones (primarily gastrin)
Which cells secrete serotonin into the bloodstream, and additional stain silver?
Neuroendocrine cells (argentaffin/ enterochromaffin cells)
Describe the direction and location of the longitudinal fibres
2 major longitudinal bands over the greater and lesser curvatures (parietal/ visceral surfaces)
Name the 3 muscular fibres located within the stomach.
Longitudinal, circular, internal oblique
Describe the direction and location of the circular fibres and what location/s they’re thickest.
Present in body/ pyloric region, thickest at pylorus which forms the pyloric sphincter
Describe the direction and location of the internal oblique fibres
Present in fundus/ cardia, closely packed in the cardiac loop, where they combine with the circular layer to form the cardiac sphincter
What centre do the lymphatics drain to from the stomach?
Coeliac lymph centre
What 4 nodes are includes in the coeliac lymph centre?
Gastric, coeliac, pancreaticoduodenal, splenic
Which plexus’s are linked to the enteric nervous system in the gut wall? (provide both names)
Myenteric (auerbach’s) and submucosal (Meissner’s)
What are the 3 main branches of the coeliac artery>
Left gastric, splenic, hepatic
What branch of the coeliac artery does the stomach receive the most amount of blood from?
Left gastric a.
What organ does the splenic artery supply blood to, and what branch does it give off?
Spleen
Left gastroepiploic a.
What organ does the hepatic artery supply blood to, and what branch/s does it give off?
Liver
Right gastric a., right gastroepiploic a.
Which curvature do the left and right gastric arteries run along. Do they anastomose?
Run along the lesser curvature, yes
Which curvature do the left and right gastroepiploic arteries run along. Do they anastomose?
Greater curvature, yes
Which vein do the venous (de-oxygenated) blood in gastric veins flow through to reach the liver?
Hepatic portal vein
Does the sympathetic or parasympathetic innervation influences increase in digestive motility?
Parasympathetic
Name the 3 sympathetic ganglia that supply the coeliac a., cranial mesenteric a., and caudal mesenteric a.
Coeliac ganglion, cranial mesenteric ganglion, caudal mesenteric ganglion
What is the vagosympathetic trunk?
The combination of sympathetic/ parasympathetic fibres travelling to the head in the thoracic cavity
Name the 4 branches the vagus nerve (parasympathetic) divides into, what region of the oseophagus does this occur at?
Left dorsal vagus n., right dorsal vagus n., left ventral vagus n., right ventral vagus n.
Occurs near the caudal 1/3 of the oesophagus
Name the branches which combine and what they’re called (from the vagus n.), and which hiatus the n.s pass through.
Right dorsal vagus n. + left dorsal vagus n. -> dorsal vagus n.
Left ventral vagus n. + right ventral vagus n. -> ventral vagus n.
Joining occurs post oesophageal hiatus
