Histology Lab 7-11 Flashcards
List the differences of the newborn and adult aortas
Newborn:
Thinner intima
Many wavy elastic fibers in media
Adult:
Thicker intima with orange fatty streaks/plaques
Less elastic and flattened media
Both have adventitia
Discuss the pathology associated w/muscular arteries
Thickening of the muscular artery wall due to combination of hypertrophy of muscular media and fibrosis of intima.
Narrowing of lumen and ischemia to tissue supplied by artery.
Identify the pathology indicated by the green arrow
Hyaline arteriolosclelrosis:
Thickening of the arteriolar wall due to deposition of proteinaceous material.
Narrow lumen
Identify the pathology
Hyperplastic arteriolosclerosis:
Changes in arterioles of patients with accelerated/malignant hypertension.
Proliferation of cells in wall of arteriole.
Luminal obstruction.
What are the key features of a medium artery?
Tunica intima
Width of tunica media = width of adventitia
Tunica media compost of smooth muscle cells
External elastic membrane
Internal elastic membrane
Name the structures in the purple and black boxes.
Purple box: External elastic membrane
Black box: Internal elastic membrane
What are the key features of an arteriole?
Well defined regular lumen.
Intima: squamous endothelial cells
Media: 2 layers of smooth muscle
Adventia
Resistance vessel
What are the key features of a capillary?
Single layer of squamous epithelial cells.
Diffusion of gases and nutrients
What are the key features of a venule?
Tunica intima: hard to distinguish
Tunica media: discontinuous layer of smooth mm
Tunica adventitia: blends into surrounding CT
Less defined irregular lumen
What are the key features of a medium vein?
Tunica intima: layer of endothelial cells and thin sub-endothelial layer composed of few smooth mm and CT
Tunica media: few layers of smooth mm and some elastin
Tunica adventitia: thickest layer, smooth mm, CT, elastin
Presence of VALVES
Contain 70% of body’s blood
What are the key features of a large vein?
Tunica intima
Tunica media: layer of circular smooth mm
Tunica adventitia: layer of longitudinal smooth mm
Holds large volume of blood.
Smooth mm facilitiates uni-directional movement of blood back to heart against gravity.
What are the key features of a lymphatic vessel?
Valves that ensure uni-diredtional flow.
Simple squamous epithelium.
Lymph in lumen.
Found in submucosa.
Discuss the pathology
Coronary artery with atherosclerosis.
Thickened tunica intima layer.
Placque with lipids and foam cells.
Narrowed lumen.
Arteriosclerosis
Hardening or thickening of the walls of arteries or arterioles.
Atherosclerosis
A form of arteriosclerosis where hardening of the walls is d/t fatty substances in the inner lining of arterial walls.
Arterioloscleriosis
Changes in arterioles that may cause ischemic damage to the tissues they supply.
Discuss the pathology
Aortic dissection:
Tear in tunica intima that leads to blood tracking into tunica media.
Consequence of age, chronic HTN, atherosclerosis, CT disorders, trauma, or vessel damage during surgery
Discuss the pathology
Likely LVH because:
Enlarged rectangular nuclei
Thicker myocytes
Fibrosis between mm cells
Discuss the pathology indicated by the purple lines
Sclerosed glomeruli:
Nephrosclerosis d/t HTN
Ischemia to glomeruli
Sclerosis of glomerulus
Atrophy of tubules
Discuss the pathology
HTN hemorrhage:
Hemorrhage in cerebral tissue
Numerous RBCs
Discuss the pathology. What is indicated by the dark blue arrow?
Purple arrows?
Invasive squamous cells carcinoma of the tongue
Dark blue arrow:
Carcinoma invading beyond basement membrane
Carcinoma cells with enlarged pleomorphic nuclei & mitotic figures
Keratin pearls
Purple arrow: Normal epithelium of the tongue
Identify the tissue
Sublingual gland:
Mixed seromucous gland
Lobules of mucus and serous-secreting cells arranged in grape-like acini.
Serous demilunes on mucous acini.
Striated ducts that resorb Na+, creating hypotonic secretion.
Interlobular ducts lined by stratified cuboidal epithelium.
What is the function of saliva?
Lubrication and protection of oral cavity.
Aids in digestion.
Serves immune role.
Identify the tissue and the components indicated.
Parotid gland
Purely serous glands
Ducts
Adipose tissue
Blood vessels
Identify the pathology
Pleomorphic adenoma of parotid gland.
Haphazard mixture of glandular and stromal tissue.
Capsule of adenoma.
Discuss the layers of the esophagus.
Mucosa:
NKSSE
Lamina propria
Muscularis mucosae: localized movements of the esophageal lumen
Submucosa:
Irregular dense CT rich in blood and lymphatics
Submucosal glands that secrete acidic mucin onto inner epithelium.
Muscularis externa:
Inner circular and outer longitudinal
Upper 1/3 all SKM
Middle 1/3 inner smooth, outer SKM
Lower 1/3 all smooth mm
Adventitia:
Irregular CT, adipose tissue, nerves and bvs.
Anchors esophagus to neighbouring structures.
Identify the layers
Identify the structure
Gastroesophageal junction:
Z-line where abrupt change from NKSSE to simple columnar
Identify the pathology in this section of the esophagus
Barrett’s Esophagus:
Metaplastic glandular epithelium
Goblet cells
Inflammation of the lamina propria and epithelium.
Metaplasia d/t backward flow of stomach contents through LES.
Increased risk of dysplastic change and development of invasive adenocarcinoma
Discuss the changes seen in this esophageal dysplasia
Barrett esophagus with metaplastic columnar epithelium.
HIgh power:
Nuclear pleomorphism
Nuclear hyperchromasia
No invasion of BM
Discuss the pathological changes seen in this esophagus
Esophageal adenocarcinoma
Low Power: normal squamous with carcinoma extending bellow it.
High Power: Enlarged pleomorphic nuclei w/ nucleoli and mitotic figures.
Squamous cell carcinoma of upper 2/3 of esophagus related to tobacco and EtOH use.
Adenocarcinoma of distal 1/3 related to GERD and Barrett esophagus.
Identify the structure
Stomach
Mucosa:
Large folds (rugae) flatten as stomach stretches.
Simple columnar epithelium w/mucin granules
Gastric pits that dip down even further to gastric glands.
Gastric glands secrete mucus, acid, digestive enzymes.
Muscularis mucosaie for localized mvmt.
Submucosa: highly vascularized and innervated CT layer
Muscularis externa: mix chyme and expel it to small intestine.
Inner oblique
Middle circular
Outer longitudinal
Serosa: moist slippery surface of mesothelial cells.
Produces thin film of serous fluid
Identify the cells
Yellow arrows: Parietal cells
Secrete HCL and intrinsic factor
Blue arrows: Chief cells
Secrete pepsinogen I & II and lipase
Identify the area
Gastroduodenal Junction:
Gradual transition from gastric mucosa to villous epithelium of duodenum.
Identify the area
Duodenum
Mucosa: broad leaf-shaped villi
Simple columnar epithelial cells (enterocytes) with microvilli
Goblet cells
Epithelium dips down to musclaris mucosae forming crypts
Submucosa:
Brunner’s glands
Muscularis externa: 2 layers
Adentitia/Serosa: some area lined by adventitia and some by serosa
Identify the structures indicated by the blue arrows
Brunner’s glands:
Secrete alkaline glycoprotien to buffer HCl from stomach
What are the functions of the duodenum?
Absorption of nutrients
Mixing, breaking down of food w/enzymes
Brush border to increase SA for absorption
Identify the pathology
Duodenal Ulcer:
Necrotic debris and inflammatory cells (ulcer slough).
No muscularis propria
Will present clinically with hematemesis or melena.
May be secondary to H.Pylori, NSAID use.
Identify the pathology
Celiac Disease:
Flattening of villi
Lengthening of crypts
Chronic inflammatory cell infiltrate in LP
Increased intra-epithelial lymphocytes
Triggered by gluten intolerance.
Clinical presentation: wt loss, anemia, steatorrhea
Identify the structure
Jejunum
Has most extensive area for secretion and absoption.
Mucosa is mostly villi and crypts.