Leslie - Microanatomy - Bird - Salivary Glands and Pancreas - Digestive

Major: parotid, mandibular, sublingual, zygomatic
(the major's parrot superbly manned the zypher)

Minor: labial, lingual, buccal, palatine
(minor labia leave boys pleased)

The differentiations are predicated on size, location, and proximity to the buccal cavity. Majors are large and located away from the buccal mucosa.

95%

Moisten, lubricate, cleanse, digest, pH, secrete antibacterial agents

Lysozyme, lactoferrin, secretory immunoglobulin (IgA)

The serous cells tend to be acidophilic despite the ER's due to all of the proteins.

The mucuous cells are described as foamy to clear, they are less acidophilic, and you can see more outlines than actual stain.

The myoepithelial cells wrap around the acinous cells at the beginning of the duct and contract - "milking" the fluid out. They are contractile cells, but they are not smooth muscle.

Major salivary glands

Simple cuboidal epithelium.

Simple columnar epithelium

Interlobular ducts are between the lobules.

The first part of the ducts are simple columnar epithelium, like in striated, but they transition to bistratified cuboidal or columnar epithelium to the intralobar ducts which are pseudostratified columnar ducts.

Intralobar ducts. These are pseudostratified columnar ducts.

Both intralobar and interlobar ducts have pseudostratified columnar epithelium.

M is the mucous gland - foamy in appearance with flattened nuclei at the base.

S is the serous demilune that has a more oval to round nucleus

The first duct connecting directly to the acinous is the intercalated ducts.

They have simple columnar epithelium.

These are striated ducts.

They have simple columnar epithelium.

You can see mitochondria below the nucleus - this gives the striated appearance.

These are secretory ducts, unlike intercalated ducts.

The striated ducts change the contents and pH by pumping Na, Cl, and phophates out of the lumen and into the CT to conserve Na.

The striated duct - the light structure on the right of the slide - and much larger than the intercalated ducts - which are surrounding the serous acinus cells.

The striated ducts are 6.
The serous acinus are 8.

This is also fig 13.27 in Bacha and Bacha
4. Mucous acinous
6. Serous acinous
7. Serous demilune
8. Striated duct

This is fig. 13.28 of Bacha and Bacha.

2. intercalated duct
4. mucous acinous
7. serous demilune
8. striated duct

This is fig. 13.21 of Bacha and Bacha

1. adipose tissue
8. mucous gland
12. serous gland
13. skeletal muscle

True. The parotid, mandibular, sublingual, and zygomatic major salivary glands are typical of different species.

Primary saliva is isotonic with plasma.
Secondary saliva is more dilute.

20-50 gallons
2-6 C

Autonomic. Parasympathetic and sympathetic can both triggers salivation.

Subepithelial means that the release of the neurotransmitter is near the target cells, then the cells diffuse out via gap junction.

Intraepithelial release is with the direct synapsing of the nerve on the target acinar cells.

Enzymes like pancreatic amylase/lipase/ribonuclease/deoxyribonuclease, proenzymes like trypsinogen/chymotrypsinogen/procarboxypeptidase, bicarbonates are all secreted through the exocrine glands of the pancreas.

This is pancreas - you can see islets of Langerhans, the endocrine cells of the pancreas. You can see them as the lighter conglomerations of cells. Sometimes, they are easier to see at lower magnifications.

The coverings are a thin, dense irregular CT capsule that extends into the parenchyma as loose CT in the septae that divide the organ into lobules. Within these lobules, are surrounding acini (adenomeres) and small ductules.

These are the endocrine portions, the islets of Langerhans.

The secretory portion of the exocrine pancreas are acinar cells.

The duct types are: intercalate (or intralobular), interlobular, the main and accessory pancreatic ducts.

The acidophilic granules are zymogen. The basal cells are basophilic due to all of the RER.

The acinous glands are pie shaped - you can see a homebaked apple pie in the upper right.

They are actually cells of the intercalated duct.

There are receptors on the epithelium of the acinar cells detecting AcH or cholycystokinin and tell the cells that they need to produce more enzyme-rich fluid.

You can see the one centroacinar cell in the middle of this exocrine acinus, there could be several at the center.

The intercalated duct is the long part extending down from the top on the left side.

The pancreatic islet is the light duct in the mid-upper right.

The acinus is in the middle quadrant of the lower half.

The cells of the intercalated ducts detect the diffuse AcH and secretin and release bicarbonate-rich fluid in response. They can be triggered at the same time or separating than the acinus glands to coordinate the release of enzyme-rich and bicarbonate-rich fluids, or just one.

The pancreatic acinus is the duct in the upper right. It has an intercalated duct that leads down to another intercalated duct. It is simple cuboidal epithelium.

You can see a centroacinar cell here

The interlobular duct is the large invagination coming in from the right.

It's made of simple tall columnar epithelium.

These are Pacinian corpuscles - there are mechanical nerve endings here in the pancreas. And more importantly, Bird likes these.