Lab 16 –Digestive Glands A560 – Fall 2015 Digestive Glands

I. Introduction II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland 2. Submandibular gland B. Pancreas C. Liver D. Gall Bladder IV. Summary

Fig 15‐1, Junqueira, 13th ed. Lab 16 –Digestive Glands A560 – Fall 2015 Learning Objectives I. Introduction II. Learning Objectives III. Slides and Micrographs 1. Review the secretory units of the salivary glands. A. Salivary Glands 1. Parotid gland 2. Understand the structure and function of the cuboidal epithelium cells 2. Submandibular gland comprising the ducts. B. Pancreas C. Liver 3. Compare and contrast the histology and exocrine function of the pancreas with D. Gall Bladder IV. Summary that of the parotid salivary gland.

4. Understand the overall organization of lobes and vasculature in the liver.

5. Understand the microvascular features specific to the liver and the function of the hepatocytes.

6. Understand the origin of bile and the system transporting it from the liver.

7. Understand the structure of the gall bladder wall and how it facilitates the organ’s function. Lab 16 –Digestive Glands A560 – Fall 2015 Comparison of Major Salivary Glands

I. Introduction II. Learning Objectives III. Slides and Micrographs Slide 132: Parotid Gland, H&E Slide 11: Submandibular Gland, PAS & AB A. Salivary Glands 1. Parotid gland 2. Submandibular gland B. Pancreas C. Liver D. Gall Bladder IV. Summary

• Compound acinar • Compound tubuloacinar • Serous acini only • Serous acini and mucuous tubules • Serous demilunes Lab 16 –Digestive Glands A560 – Fall 2015 Excretory Pathway from Salivary Glands I. Introduction II. Learning Objectives III. Slides and Micrographs A. Salivary Glands Secretory cells 1. Parotid gland 2. Submandibular gland B. Pancreas Intercalated ducts: small/closed‐appearing lumen (generally smaller than acinus); lined C. Liver with simple squamous or cuboidal epithelium; often surrounded by myoepithelial cells D. Gall Bladder Intralobular IV. Summary Striated (intralobular) ducts: larger, open lumen; lined with simple cuboidal (or columnar) cells with basal striations

Interlobular ducts: in septa; increasing size; and epithelium transitioning from simple cuboidal to columnar epithelium; may be stratified

Excretory (lobar) ducts: largest; from superficial and deep lobes of gland; stratified “Excretory” cuboidal or maybe columnar epithelium Lab 16 –Digestive Glands A560 – Fall 2015 Slide 132: Parotid Gland, H&E I. Introduction II. Learning Objectives III. Slides and Micrographs A. Salivary Glands capsule 1. Parotid gland 2. Submandibular gland B. Pancreas septa divide C. Liver lobules of glands D. Gall Bladder IV. Summary

excretory duct

lobule

striated ducts presence of ducts distinguishes organ as exocrine gland – so not to be confused with any of the lymphoid structures Lab 16 –Digestive Glands A560 – Fall 2015

I. Introduction Slide 132: Parotid Gland, H&E II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland 2. Submandibular gland B. Pancreas C. Liver D. Gall Bladder septum IV. Summary

striated ducts adipose excretory duct Lab 16 –Digestive Glands A560 – Fall 2015 Slide 132: Parotid Gland, H&E I. Introduction II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland striated duct 2. Submandibular gland parenchyma B. Pancreas is composed C. Liver of serous D. Gall Bladder acini only IV. Summary

adipose

excretory duct in septum Lab 16 –Digestive Glands A560 – Fall 2015 Slide 132: Parotid Gland, H&E

I. Introduction II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland 2. Submandibular gland striated duct with faint B. Pancreas “striation”’in basal half of C. Liver cell perpendicular to D. Gall Bladder lumen IV. Summary Lab 16 –Digestive Glands A560 – Fall 2015 Slide 11: Submandibular Gland, PAS AB I. Introduction II. Learning Objectives III. Slides and Micrographs A. Salivary Glands parenchyma consists 1. Parotid gland of both serous and 2. Submandibular gland mucous cells B. Pancreas C. Liver D. Gall Bladder IV. Summary Dark staining cells = mucous cells Light staining cells = serous cells

striated duct Lab 16 –Digestive Glands A560 – Fall 2015 Slide 11: Submandibular Gland, PAS AB

I. Introduction II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland 2. Submandibular gland B. Pancreas C. Liver D. Gall Bladder IV. Summary

Notice the difference in tissue lining lumen between duct and vessel

excretory duct Lab 16 –Digestive Glands A560 – Fall 2015 Slide 72: Submandibular Gland, H&Phloxine

I. Introduction II. Learning Objectives III. Slides and Micrographs A. Salivary Glands Mucous cells 1. Parotid gland 2. Submandibular gland Mucous = Adj. B. Pancreas Mucus = Noun C. Liver D. Gall Bladder IV. Summary Serous cells

Serous demilune: “half moon” shape of serous portion of striated gland surrounding mucous portion ducts

Serous acini secrete non‐glycosylated protein products and stain strongly due to their abundant rER and secretory granules; Mucous acini secrete mucus (mucopolysaccharide) and contain little rER so tend to be poorer‐staining with most general stains Lab 16 –Digestive Glands A560 – Fall 2015 Slide 15: Pancreas, H&E I. Introduction II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland 2. Submandibular gland like the salivary glands, B. Pancreas notice organization into of C. Liver pancreas (compound acinar) D. Gall Bladder into lobules, separated by IV. Summary CT septa; however, notice the lack of conspicuous striated (intralobular) ducts in the lobules as were seen in the salivary glands Lab 16 –Digestive Glands A560 – Fall 2015

I. Introduction Slide 154: Pancreas, H&E II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland pancreas is divided into 2. Submandibular gland excretory and endocrine B. Pancreas portions: C. Liver D. Gall Bladder Dark cells = IV. Summary secretory acini (excretory)

Light clusters of cells = Pancreatic islets (endocrine) (Islets of Langerhans) Lab 16 –Digestive Glands A560 – Fall 2015 Slide 154: Pancreas, H&E I. Introduction II. Learning Objectives III. Slides and Micrographs intralobular excretory duct A. Salivary Glands (only one type of intralobular 1. Parotid gland duct, unlike in salivary glands) 2. Submandibular gland B. Pancreas C. Liver D. Gall Bladder IV. Summary

Secretory acini (exocrine)

pancreatic islet or islet of Langerhans (endocrine) Lab 16 –Digestive Glands A560 – Fall 2015 Slide 154: Pancreas, H&E I. Introduction II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland 2. Submandibular gland B. Pancreas secretory C. Liver acinus D. Gall Bladder IV. Summary

serous acini of the exocrine pancreas have 5‐10 cells facing central lumen;apicalendsare eosinophilic due to secretory granules; basal ends are basophilic due to nucleus and rER Lab 16 –Digestive Glands A560 – Fall 2015

I. Introduction Slide 24: Liver & GB, Masson Trichrome II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland 2. Submandibular gland B. Pancreas C. Liver D. Gall Bladder larger spaces = portal triads IV. Summary

smaller spaces = central veins Lab 16 –Digestive Glands A560 – Fall 2015

I. Introduction Slide 141: Liver, H&E II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland 2. Submandibular gland portal B. Pancreas triad C. Liver D. Gall Bladder hepatic IV. Summary artery

bile duct Lab 16 –Digestive Glands A560 – Fall 2015

I. Introduction Slide 141: Liver, H&E II. Learning Objectives III. Slides and Micrographs A. Salivary Glands Portal Tract/Triad 1. Parotid gland hepatic portal vein 2. Submandibular gland B. Pancreas C. Liver D. Gall Bladder IV. Summary

hepatic artery

bile duct Lab 16 –Digestive Glands A560 – Fall 2015 Slide 24: Liver, Masson Trichrome I. Introduction II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland 2. Submandibular gland B. Pancreas C. Liver D. Gall Bladder hepatic IV. Summary lobule

central vein Lab 16 –Digestive Glands A560 – Fall 2015 Slide 29: Liver, H&E I. Introduction II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland 2. Submandibular gland central vein B. Pancreas C. Liver D. Gall Bladder portal triad IV. Summary Lab 16 –Digestive Glands A560 – Fall 2015 Slide 24: Liver, Masson Trichrome I. Introduction II. Learning Objectives III. Slides and Micrographs Kupffer cell A. Salivary Glands (macrophage) 1. Parotid gland in sinusoid 2. Submandibular gland B. Pancreas C. Liver hepatocytes D. Gall Bladder IV. Summary

hepatic sinusoids lined by endothelial cells Lab 16 –Digestive Glands A560 – Fall 2015 Slide 24: Liver, Masson Trichrome I. Introduction II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland 2. Submandibular gland B. Pancreas C. Liver D. Gall Bladder lipofuscin IV. Summary Lab 16 –Digestive Glands A560 – Fall 2015 Slide 94: Gallbladder, Trichrome I. Introduction II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland 2. Submandibular gland B. Pancreas C. Liver D. Gall Bladder IV. Summary serosa on free surface; covered by adventitia where bound by liver

muscularis lamina propria lumen mucosa

note the lack of muscularis mucosae and submucosa; the lamina propria is directly on the muscularis layer Lab 16 –Digestive Glands A560 – Fall 2015

I. Introduction Slide 94: Gallbladder, Trichrome II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland 2. Submandibular gland B. Pancreas C. Liver D. Gall Bladder IV. Summary

mucosal fold/ruga: transient folds of mucosa; disappear when gallbladder is full Lab 16 –Digestive Glands A560 – Fall 2015

I. Introduction Slide 94: Gallbladder, Trichrome II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland 2. Submandibular gland B. Pancreas C. Liver D. Gall Bladder IV. Summary very thin basement membrane

simple columnar epithelium, with NO goblet cells Lab 16 –Digestive Glands A560 – Fall 2015

I. Introduction Slide 105: Gallbladder, H&E II. Learning Objectives III. Slides and Micrographs A. Salivary Glands 1. Parotid gland epithelium 2. Submandibular gland B. Pancreas C. Liver D. Gall Bladder IV. Summary

muscularis

lamina propria

serosa/adventitia Lab 16 –Digestive Glands A560 – Fall 2015

I. Introduction II. Learning Objectives III. Slides and Micrographs Gallstones A. Salivary Glands 1. Parotid gland 2. Submandibular gland B. Pancreas C. Liver D. Gall Bladder IV. Summary Lab 16 –Digestive Glands A560 – Fall 2015

I. Introduction II. Learning Objectives EMs to Examine III. Slides and Micrographs A. Salivary Glands 1. Parotid gland 2. Submandibular gland Fig 16‐4: Serous and mucous cells B. Pancreas C. Liver Fig 16‐10: Pancreatic acinar cells D. Gall Bladder IV. Summary Fig 16‐14: Hepatocytes, perisinusoidal space, and bile canaliculi Fig 16‐20: Gallbladder Lab 16 –Digestive Glands Common Confusion: A560 – Fall 2015 Parotid gland vs. Pancreas I. Introduction II. Learning Objectives Parotid Gland: major salivary gland located in front of ear; III. Slides and Micrographs almost exclusively serous cells that produce a thin watery secretion rich in enzymes (e.g., amylase) A. Salivary Glands 1. Parotid gland Look for: (1) striated (intralobular) ducts are readily 2. Submandibular gland visible; (2) surrounded by CT capsule with defined septa; B. Pancreas (3) adipocytes may be present between lobules C. Liver D. Gall Bladder IV. Summary Slide 132, Parotid Gland

Pancreas: exocrine and endocrine gland located in upper left of abdomen; exocrine portion is purely serous and empties into the duodenum

Look for: (1) pale‐staining pancreatic islets (endocrine); (2) ducts are fewer and less readily seen; (3) surrounded by loose CT or very thin capsule with delicate septa; (4) at higher magnification, pale‐staining centroacinar cells (where duct inserts into acinus) may be seen

Slide 44, Pancreas Lab 16 –Digestive Glands Common Confusion: A560 – Fall 2015 Pancreas vs. Spleen I. Introduction II. Learning Objectives Pancreas: exocrine and endocrine gland located in upper III. Slides and Micrographs abdomen; exocrine portion is purely serous and empties into the duodenum A. Salivary Glands 1. Parotid gland 2. Submandibular gland Look for: (1) exocrine gland, so ducts are present; (2) pale‐ B. Pancreas staining pancreatic islets (endocrine) have homochromatic appearance; (3) at higher magnification, cells arranged in C. Liver acinar configuration D. Gall Bladder IV. Summary Slide 154, Pancreas

Spleen: highly‐vascular abdominal organ with abundant lymphoid tissue; filters the blood, providing immune functions and removal/destruction of old or faulty red blood cells

Look for: (1) no exocrine tissue, so lacks ducts; (2) white pulp has heterochromatic staining, e.g., pale germinal centers surrounded by dark mantle zone; (3) no acini present; (4) numerous trabeculae

Slide 68, Spleen