Flashcards in GI Secretions (review w/ handout 10/21 11a) Deck (54)
fat/prot in duodenal lumen
leads to increased CCL release from duodenal mucoasa
CCK acts on panc acinar cells
increased secretion of pancreatic dig enzy into duodenal lumen
Exocrine pancreas structure
Acinar cells make the enzymes and duct cells secrete a water/bicarbonate rich solution
**** no myoepithelial cells
rate of secretion much less variable
in GB: contraction
pancreas: stim acinar secretion
in stomach: reduced emptying (inhibitory)
sphincter of Oddi: relaxation
Protein, carbohydrate, lipid absorption and digestion
Matching of nutrient delivery to digestive and absorptive capacity
CCK released from??????
redo this card
trypsin controls releasing and monitoring peptide
trypsin prefers to act on prot/aa breakdown
Lots of fat? want CCK production to help breakdown fat
So shuts off trypsin protein breakdown
Monitor peptide monitors level of protein in duodenum
turn off CCK
cAMP and Ca in acinar cells
in epi/acinar cells, cAMP and Ca do the same thing
both stim increased secretion
Granules containing zymogens fuse with membrane and secrete contents
trypsin is inactive from pancrease (trypsinogen)
Also released is a trypsin inhibitor.
Trypsin becomes activated in the duodenal lumen when trypsinogen is cleaved by enzymes (enterokinases) located on the surface of enterocytes
Activated trypsin then autoactivates more trypsinogen along with most of the other pancreatic enzymes
acts by increasing cAMP levels in the duct cells. The release of secretin is enhanced by CCK
Panc vs salivary differences??????
salivary secretions are susceptible to changes in flow rate, pancreatic secretions are not
no myoepithelial cells in panc
Panc: neuronal and humorally
salivary acinus is very vascular and increased blood flow results in a dilute saliva that is modified by duct cells. Salivary ducts, on the other hand, are fairly impermeable to water.
Pancreatic acini are not as vascular and respond to ACh and CCK. Ductal cells actively secrete a water and a bicarbonate rich solution in response to secretin.
Saliva is rich in KHCO3 whereas pancreatic juice is rich in NaHCO3.
Salivary gland diseases
Sjögren’s Syndrome (autoimmune disease, inflammation)
Salivary Lymphoepithelial Lesion
Xerostomia or dry mouth
-Mixed Tumor (pleomorphic adenoma)
diverse microscopic pattern
Islands of cuboidal cells arranged in ductlike structures
Loose chondromyxoid stroma, connective tissue, cartilage (arrows) and even osseous tissue are observed
Warthin's tumor (benign papillary cystadenoma lymphomatosum)
the second most common benign tumor of the parotid gland
It accounts for 2-10% of all parotid gland tumors
Bilateral in 10% of the cases
may contain mucoid brown fluid in FNA
ID by aspiration
epithelial component (papillary fronds), stains pink , shows granularity, can undergo metaplasia but rare
and lymphoid component
Both lymphoid and oncocytic epithelial elements must be present to diagnose Warthin’s
can be bilateral
rare malignant potential
Similar to Pleomorphic Adenoma except no mesenchymal stromal component
Predominantly an epithelial component
Basal cell adenoma
uniform basaloid epithelial cells with a monomorphous pattern.
The arrangement of tumor cells may be trabecular (rod-like), tubular or solid.
Histologically, these tumors are distinguished from pleomorphic adenomas by their absence of stroma and the presence of a uniform epithelial pattern.
Malignant neoplasms by increasing freq
Mucoepidermoid Carcinoma (mucin+)
Polymorphous Low-grade Adenocarcinoma
Adenoid Cyctic Carcinoma
Clear Cell Carcinoma
Acinic Cell Carcinoma (no glycogen, fat & mucin, 3% maligant and bilateral)
Features suggestive of malignancy
Fixed to Overlying Skin or mucosa
Ulceration of skin or mucosa
Rapid Growth; Growth Spurt
Pain, often severe
Facial N. Palsy
pain and palsy go together often
size of T2
T2: 2 cm
MECs contain two major elements: mucin-producing cells and epithelial cells (Epidermoid and Mucinous components).
MEC is divided into low-grade (well differentiated) and High-grade (poorly differentiated).
Stains that ID mucous
Adeonid cystic carcinoma
Adenoid cystic carcinoma with Swiss cheese pattern.
It is the second-most common malignant tumor of the salivary glands.
ACC is the most common malignant tumor found in the submandibular, sublingual, and minor salivary glands.
against nerve: risk of spread, pain, palsy
Carcinoma Ex-mixed Tumor/Malignant Mixed Tumor/Metastasizing Mixed Tumor
Salivary Duct Carcinoma
Basal cell Adenocarcinoma
Squamous Cell Carcinoma
fatty rich food
linked to gallstones
acute or chronic
Sx: include upper abdominal pain, nausea/vomiting, weight loss and steatorrhea (oily, smelly stool)
Panc cancer endocrine
Gastrinoma (Zollinger-Ellison Syndrome)
Glucagonoma – usually large, often mets, 70% malignant
Insulinoma – the most common pancreatic neuroendocrine tumors
Nonfunctional islet cell tumors (NICT) – Usually malignant and hard to detect; don't produce insulin?
Somatostatinoma – occur anywhere in the pancreas or doudenum
VIP-Releasing Tumor – usually in the body and tail of the pancreas
Panc cancer exocrine
Acinar Cell Carcinoma – Rare, leads to overproduction of lipase
Adenocarcinoma – 90% of all pancreatic cancer starts in duct
Adenosquamous carcinoma - forms glands that flatten as it grows
Intraductal Papillary-Mucinous Neoplasm – fingerlike projections into the duct, prelude to malignancy
Mucinous Cystadenocarcinoma – rare malignant spongy cystic tumor
Pancreatoblastoma – Rare, occurs in kids