Saliva 1 Flashcards
What can cause a reduction in salvia?
- head and neck radiotherapy
- autoimmune disease Sjogrens syndrome
- Medications
What does lack of saliva do to the tongue?
Can cause it to become fissured
Salivary function is tested by a technique called _____.
Scintigraphy = Iv injection of isotope or technetium that binds to Na-K-Cl membrane transport system of acinar cells of salivary glands.
What is congenital salivary aplasia?
Missing or underdeveloped salivary glands
True or false, Salivary gland disorders are rare and Genetic in origin.
True
Briefly describe other disorders that can accompany salivary gland agenesis…..
It can occur in isolation or it can be accompanied by other disorders of the ectoderm or 1st brachial arch *such as abnormalities in hair, nails, missing teeth or deafness/
What are the 7 functions of saliva?
- Protection = Mucins (glycoproteins responsible for lubricating mucosal surface and providing protective barrier.
- Buffering = Bicarbonate (buffers acids in mouth)
- Tooth integrity = Proline rich proteins & Statherin (calcium binding proteins contribute to enamel maturation and remineralization)
- Antimicrobial = Lysozyme, peroxidase, defensins, histatins & IgA)
- Tissue repair = Growth Factors
- Digestion = Amylase & Lipase
- Taste = Molecules must dissolve in water to be transported to taste bud.
Salivary glands are classified as a ______ gland.
Exocrine = uses a duct
Normal daytime salivary flow rate = ?
.3-.4ml/min
normal volume of saliva in mouth = ?
0.8-1.1ml
What are the 3 major salivary glands?
Parotid = IX Submandibular = VII Sublingual = VII
What are the minor salivary glands?
Von Ebners gland = IX
Labial
Palatal
Buccal & lingual
_____ Contributes around 60% of salvia.
parotid = whole mouth saliva (watery saliva)
____ contributes around 25% of salvia.
Submandibular
______ contributes around 7-8% of saliva.
submandibular and minor glands
The parotid gland is a ________ gland and the major source of ____P_>
Pure serous = watery saliva *major source of amylase
The Submandibular and sublingual gland are ______ glands.
Mixed serous/mucous glands
Von Ebner’s gland is a ______ gland and the major source of _____.
Pure serous gland. Main source of lipase.
The other minor glands are _____ glands and major source of _____.
Pure serous glands. Major source of Mucins (lubrication)
Where does parotid gland secrete to?
Stensons duct, which opens opposite the 2nd max molar.
Where does submandibular gland secrete?
empties into oral cavity via Whartons duct on the lingual frenum.
Where does the sublingual gland secrete?
empties into a series of ducts on the sublingual fold behind Whartons duct, called the Bartholins and Rivinus’s ducts.
Saliva glands are made up of what 2 division?
Stroma = supporting role (organizing gland into lobes) Parenchyma = does the characteristic work of given gland (makes and secretes salvia)
Stroma is made of _______.
Connective tissue
Parenchyma is made of _____.
Epithelium
The stroma includes the ____ & ____.
Capsule and septum
What is the major cell of the Stroma?
Fibroblasts = makes collagen (b/c its made from CT!)
What other 4 items are found in the stroma?
- blood vessels = supply to parenchyma
- Nerve fibers = supply parenchyma
- Plasma cells = secret antibodies
- fat cells = increase with age
What are the 2 main parts of the Parenchyma?
- Secretory portion (acini) = composed of individual acinar or secretory cells that make saliva.
- Ducts
What are the 2 main types of Acinar cells and the 3 types of endpieces they make up?
Serous and Mucous acinar cells
- serous endpieces
- mucous endpieces
- mixed end pieces
Order of salvia flow from Acini….
Acini —-> intercalated ducts —> Striated/secretory ducts —-> excretory ducts. * ducts get progressively larger!
When do the salivary glands develop?
Parotid = 6 weeks IU
Submandibular = end of 6th week IU
Sublingual and minor = 8-12 weeks IU
What is the origin of the salivary glands?
PARENCHYMA
- parotid = ectoderm
- Submandibular = ecto or endoderm
STROMA = Neural crest
As salivary glands develop and branch, the structure that will become the ducts hollow out in a process known as _____.
Cavitation
What are the 4 steps of Salivary gland development?
- Protrusion of Epithelial cells in mesenchyme & bud formation
- Strong epithelial-mesnchymal interactions
- Branching morphogenesis
- Cavitation
Before branching in salivary gland development occurs, each cells is adhered to its neighbor by a cell adhesion molecule called ______.
e-cadherin
* Cadherin disappears as cleft progresses
_____ is used to “knock down” the expression of clefting.
Cleftin
What induces the expression of cleftin?
Fibronectin
What 2 actions does cleftin participate in?
Suppresses e-cadherin expression & up regulates snail2
What is snail2?
Transcription factor that promotes clefting
Acinar cells ______ salvia, while Ducts _____ & _____ certain components of salvia.
Secrete, Secrete & Resorb
Acinar cells secrete ___________ that is _________.
Primary saliva that is Isotonic
The fluid in the secondary saliva is ______.
Hypotonic!
Salivary function is almost entirely under ____ control.
Neural
Salivary glands are supplied by the ____ system.
Autonomic
- sympathetic
- parasympathetic
- Cell bodies of pre-ganglionic parasympathetic neurons located in brainstem, send axons out of the brain in the 7th and 9th cranial nerve that will synapse on post-ganglionic neurons near each gland.
The sympathetic supply to salivary glands originates in the ______.
IML —–> Superior cervical ganglion –> Salivar glands
The _____ system is responsible for protein secretion.
Sympathetic
Activation of Sympathetic NS alone produces _________________.
a protein laden, viscous secretion that is not voluminous
