Term
| Salivary Glands are what type of gland? |
|
Definition
|
|
Term
| What is a secretory end piece? |
|
Definition
| -Terminal secretory end structures consisting of groups of cells surrounding a central lumen -Basal lamina surrounds entire structure |
|
|
Term
| What are the 2 types of secretory cells? |
|
Definition
|
|
Term
| What is located between the secretory cells and the surrounding basal lamina? |
|
Definition
|
|
Term
| What can are found in aging glands? |
|
Definition
|
|
Term
| What type of secretory cells are normally found in acini? |
|
Definition
|
|
Term
| What type of secretory cells are normally found in tubular end pieces? |
|
Definition
|
|
Term
| Structure of mixed serous-mucous glands? |
|
Definition
| Mucous tubules open into proximal duct system (intercalated) while small groups of serous cells (demilunes) line the outer surface of the tubules and their secretion reaches lumen though canaliculi between mucous cells |
|
|
Term
| Serous cells are shaped how? |
|
Definition
| Pyramidal and arranged in acini |
|
|
Term
| How are serous cells organized? |
|
Definition
| In a single layer around small central lumen of the acinus |
|
|
Term
| Which end of a serous cell is in contact with lumen? Its periphery? |
|
Definition
| Apical lines the lumen. Basal lined periphery |
|
|
Term
| Serous cells have what kind of nucleus? |
|
Definition
| Round, located near basal side. |
|
|
Term
|
Definition
Basal side and nucleus are basophilic (has lots of RER).
Apical side has zymogen granules and stain eosiniphilic. Cell borders are poorly defined. |
|
|
Term
| Serous cells use junction complexes like tight junctions to separate apical and basal domains. True or false? |
|
Definition
| True. Remember these are a type of epithelial cell! |
|
|
Term
|
Definition
| Finger like extensions of lumen located between adjacent serous cells. Serous cells contain many desmosomes and gap junctions along its length. Microvilli project from lateral cell membrane in lumen of canaliculi. |
|
|
Term
| How are mucous cells arranged? |
|
Definition
| In elongated secretory end structures called mucous tubules. |
|
|
Term
| All mucous cells contain canaliculi. True or false? |
|
Definition
| FALSE. The only ones that do are covered in serous demilune cells. |
|
|
Term
| What kind of nucleus do mucous cells have? |
|
Definition
| Flat and compressed against the basal membrane due to large amounts of secretory granules. |
|
|
Term
| What do mucigen granules contain? |
|
Definition
| Mucous glycoproteins call Mucins. |
|
|
Term
|
Definition
| Strongly hydrophilic glycoproteins found in mucigen granules. Largely carbohydrate. Suck up water to form mucous. Can be stained with PAS. |
|
|
Term
| What are myoepithelial cells? |
|
Definition
| Non-secretory cells found between basal cell membrane of secretory cells and the basement membrane that surround tubules and acini. Also found on outer surface of intercalated ducts |
|
|
Term
| What are the characteristics of myoepithelial cells? |
|
Definition
| Octopus shaped, contain myofilaments, dense bodies and attachments plaques. Joined to adjacent cells by desmosomes. Play a possible contractile role in secretion. |
|
|
Term
| In aging glands, what do oncocytes replace? What do the look like? What is their function? |
|
Definition
| They replace serous cells and duct lining cells. Cuboidal to low columnar and eosinophilic. Their function is unknown. |
|
|
Term
| What are the 3 components of salivary glands? |
|
Definition
| Terminal secretory end structures, Ducts, and Connective tissue stroma |
|
|
Term
| Saliva formation occurs in how many stages? |
|
Definition
|
|
Term
| What is the first stage of saliva formation? |
|
Definition
| Primary saliva produced by cells in S.E.P's and intercalated ducts. It is isotonic, contains most components and all water (which comes in via SEP's) |
|
|
Term
| What is the second staged of saliva formation? |
|
Definition
| Primary saliva is modified in striated and excretory ducts by reabsorption and secretion of electrolytes. Saliva that leaves is Hypotonic. |
|
|
Term
| How are secretory protein granules released? |
|
Definition
| NE binds to B-adrenergic receptor. G-protein, andeyl cyclase, cAMP, protein kinase A, and cascade of phosphorylation lead to granule exocytosis. Fuse with apical membrane and release contents. |
|
|
Term
| What part of the nervous system controls protein secretion? |
|
Definition
| Sympathetic (NE binds to B-adrenergic receptors) |
|
|
Term
| What part of the nervous system regulates water secretion by SEP's? |
|
Definition
| Both parasympathetic and sympathetic. Ach binds to cholinergic wile NE binds to A-adrenergic receptors to activate release of CA from intracellular stores (Via IP3) |
|
|
Term
| What is the main mechanism for water secretion? |
|
Definition
| Increased Ca concentration opens Cl channels in apical cell mem. and K channels in basal mem. Activates basolateral Na/K/2Cl cotransporter. Cl efflux into lumen drags Na with it. Large amount of particles in lumen, cause water to move out. |
|
|
Term
| Fluid secretion is driven by what? |
|
Definition
| Active transport of electrolytes |
|
|
Term
| What is a second mechanism for fluid secretion? |
|
Definition
| Cl cause HCO3 to move into lumen. Na/H+ coupled antiport pump restores pH after acidification. pH of saliva increases as flow increases. |
|
|
Term
| What is the flow if the ductal system, starting from the SEP's? |
|
Definition
| 1. SEP's drain into small intercalated ducts. 2. These drain into intralobular striated ducts. 3. These drain into interlobular excretory ducts. 4. These open onto mucosal surface |
|
|
Term
| Which ducts receive saliva directly from SEP's? |
|
Definition
|
|
Term
| What type of epithelium lines intercalated ducts? |
|
Definition
| Simple low cuboidal and contain a small amount of RER. |
|
|
Term
| Where are intercalated ducts most easily identifiable? |
|
Definition
| In the Parotid gland, where they are the longest |
|
|
Term
| What do intercalated ducts contribute to saliva? |
|
Definition
| Antibacterial substances such as lysozyme and lactoferrin |
|
|
Term
| Which dust to intercalated ducts drain into? |
|
Definition
| Intralobular striated ducts |
|
|
Term
| Where are striated ducts located? |
|
Definition
| Within lobules. Easily identifiable because they are largest intralobular structures |
|
|
Term
| What type of epithelium lines striated ducts? |
|
Definition
| Simple columnar. Have central nucleus and eosinophilic cytoplasm |
|
|
Term
| Striated ducts look similar to what? |
|
Definition
|
|
Term
| What causes the striations in striated ducts? |
|
Definition
| Deeply folding basal plasmalemma of the lining cells where parallel rows of elongated mitochondria reside. |
|
|
Term
| Where are striated ducts the longest? |
|
Definition
| In the sub-mandibular gland |
|
|
Term
| The apical cytoplasm of striated duct cells contain what? |
|
Definition
| Secretory granules and electron-lucent vesicles. Granules contain Kallikreins, vesicles might play role in endocytosis of stiff in lumen. |
|
|
Term
| Striated ducts drain into what? |
|
Definition
| Interlobular excretory ducts |
|
|
Term
| Where are excretory ducts located? |
|
Definition
| Between lobules of glandular parenchyma (interlobular) |
|
|
Term
| Excretory ducts are surrounded by what? |
|
Definition
| Collagenous connective tissue |
|
|
Term
| What type of epithelium lines excretory ducts? |
|
Definition
| Pseudostratified or stratified columnar. |
|
|
Term
| What are the types of cells located in excretory ducts? |
|
Definition
| Columnar cells, smaller basal cells, some goblet cells and small amounts of brush (nerve receptor)and dendritic antigen presenting cells. |
|
|
Term
| What type of epithelium lines the excretory ducts are they approach the oral mucosa? |
|
Definition
| Stratified squamous. This then merges with the epithelium of the mucosa. |
|
|
Term
| Saliva is isotonic withing the SEP's and intercalated ducts. True or False? |
|
Definition
| True. It remains isotonic through intercalated ducts where Lysosyme and lactoferrin may be secreted. Becomes hypotonic as it passes through striated and excretory ducts. |
|
|
Term
| How does saliva become hypotonic? |
|
Definition
| More Na and Cl are reabsorbed from saliva than K and HCO3 is secreted. This occurs mostly in striated ducts. |
|
|
Term
| What is the deciding factor of the final electrolyte composition of saliva? |
|
Definition
| Its flow rate along the ducts. Very high flow rates = higher NA + CL + HCO3 lower K (This is due to shorter time spent in contact with ducts plus HCO3 is driving force for greater secretion) |
|
|
Term
| What regulates electrolyte reabsorbtion and secretion of saliva? |
|
Definition
| The ANS and aldosterone (causes NA reabsorbtion in saliva, sweat and urine)) |
|
|
Term
| What type of connective tissue surrounds MAJOR salivary glands? |
|
Definition
| Collagenous CT CAPSULE. Extends into paranchyma as septae or trabeculae and divide gland into lobules |
|
|
Term
| What type of connective tissue surrounds minor salivary glands? |
|
Definition
| Areolar CT. They lack a distinct capsule |
|
|
Term
| Plasma cells secrete what in salivary connective tissue? |
|
Definition
| Dimeric IgA which is released into the stroma. The IgA are uptaked by epithelial cells via secretory component receptors and released with saliva. Has a secretory components that keeps it from being destroyed. |
|
|
Term
| What type of cells increase in number within the glands as one ages? |
|
Definition
| Adipocytes, particularly in the PAROTID gland. |
|
|
Term
| What are the major salivary glands? |
|
Definition
| Parotid, Submandibular and Major sublingual |
|
|
Term
| What type of gland is the Parotid? |
|
Definition
| Purely serous acini. Has very LONG intercalated ducts and SHORT striated ducts. |
|
|
Term
| What is the main excretory duct of the Parotid? |
|
Definition
|
|
Term
| What type of gland is the Submandibular? |
|
Definition
| Mainly serous acini with some mucous tubules. Has SHORT intercalated ducts and LONG striated ducts. |
|
|
Term
| What is the main excretory duct of the submandibular? |
|
Definition
|
|
Term
| What type of duct is the Major Sublingual? |
|
Definition
| Mostly mucous with some serous acini. Almost no intercalated and striated dicts. |
|
|
Term
| What is the main excretory duct of the Major Sublingual? |
|
Definition
| Bartholin's duct, which sometimes joins Wharton's or opens onto the sublingual fold. |
|
|
Term
| What type of glands are the minor salivary glands? |
|
Definition
| Almost purely mucous EXCEPT von Ebner's glands which are serous. |
|
|
Term
| What are von Ebner's lands associated with? |
|
Definition
| The circumvallate and foliate papillae |
|
|
Term
| The minor salivary glands are found throughout the oral mucosa EXCEPT for? |
|
Definition
| Gingivae, anterior hard palate and the anterior 2/3 of the tongue. Produce 7-10% of saliva. |
|
|
Term
| What is the daily saliva production range? |
|
Definition
|
|
Term
| What is the saliva flow rate while eating? |
|
Definition
| "Stimulated flow rate" is 2-5 mL per min |
|
|
Term
| What is the saliva flow rate while resting? |
|
Definition
| "Non-stimulated flow rate" is 0.2-0.4 ml per min |
|
|
Term
| What is the stimulated flow rate for the Parotid gland? |
|
Definition
| 0.5-2 mL per min. Similar to submandibular and sublingual. |
|
|
Term
| The viscosity of whole saliva depends on what? |
|
Definition
| The ratio of saliva being produced by each gland. Parotid and SubM are watery, SubL is more viscous and minor glands are all mucous. |
|
|
Term
| What percentage of saliva is produced by the major glands? |
|
Definition
|
|
Term
| What type of saliva does the Parotid produce? |
|
Definition
Clear watery saliva rich in enzymes like amylase, proline-rich proteins and glycoproteins.
SubM is similar but also contains mucins. |
|
|
Term
| What are the major components of saliva? |
|
Definition
| Water (90%), amylase, lysozyme, secretory IgA, glycoproteins (mucins) and electrolytes (Na, K, Cl, HCO3, Ca, HPO4). |
|
|
Term
| What are the 6 functions of saliva? |
|
Definition
1. Lubrication
2. Mechanical washing
3. Tooth surface protection
4. Antimicrobial activity
5. Buffering
6. Digestion |
|
|
Term
| How does saliva enhance lubrication for swallowing and speaking? |
|
Definition
|
|
Term
| How is mechanical washing enhanced? |
|
Definition
| By the large water volume |
|
|
Term
| How is tooth protection enhanced? |
|
Definition
| Glycoproteins form and enamel pellicle which binds to tooth surface. Bind calcium, forming supersaturated solution of Ca and P ions. Reduces dissolving of enamel and increases remineralization. |
|
|
Term
| 6 antimicrobial factors of saliva? |
|
Definition
1. Mucous barrier protects mucosa
2. Lysozyme kills some bacteria
3. Thiocynate ions do... something
4. Lactoferrin enhances Ig's
5. Serum Ig's enter in gingival fluid
6. IgA coats everything and prevents adherence of microorganisms. |
|
|
Term
|
Definition
1. Bicarbonate and phosphate ions neutralize acids in foods and from bacteria
2. Prevents growth of bacteria that need a special pH |
|
|
Term
| How does saliva aid in digestion? |
|
Definition
1. Amylase breaks down carbs into glucose and maltose.
2. Lipase breaks fat down.
3. Helps taste by dissolving food.
4. Neutralizes gastric juice.
5. Enhances bolus formation. |
|
|
