Salivary Glands Flashcards
What are salivary glands?
Tubulo-acinar exocrine glands -700-1000 minor salivary glands -3 paired set of major glands
What are the 3 major salivary gland pairs?
- Parotid 2. Submandibular 3. Sublingual
What examples of pathology can occur with saliva glands?
- Congenital issues (aplasia) 2. Metabolic issues (sialadenosis) 3. Reactive (Nec, Sialametoplasia) 4. Immune (sjogrens Syndrome) 5. Inflammatory (non neoplastic and neoplastic)
How many salivary gland tumours are there?
WHO 2017 H&N tumours include 13 benign and 24 malignant tumours of salivary glands
What is the function of salivary glands?
- moistens MM (friction reduction) 1.5 L a day 2. Taste 3. Digestion (amalyse and lipase) 4. Protective function (IgA, glycoproteins) 5. Buffering capacity (K, Na, bicarb) 6. Thromboplastin (tissue factors - GFs (EGF, TGF, FGFS) to promote repair and clotting
When do saliva glands begin to develop?
Parotid: 6-8th week from ectoderm (1 and 2nd brachial arches) Submandibular 6th week from endoderm Sublingual 8th week from endoderm Primative glandular tissue engages mesenchymal layer Cell signals to form functional gland and secretory unit first. Then terminal buds and acini in 14th week. The sublingual and Subman incapsulate first, the parotid does later to allow for lymph, BV/N to infiltrate the region. innervated by the para and sympathetic.
What are the main components structurally of a salivary gland?
- Capsule - myoepthelial cells 2. Acini 3. Ducts They are avascular
What are acini?
The secretory/functional units of a salivary gland -can be serous (amalayse) or mucus (sialomucin) o r mixed
- Serous acini are 8–12 pyramid‐shaped cellswith centered basal nucleus around the lumen of the intercalated ducts. secrete watery saliva (amalayse). basophilic
- Mucous acini have clear cytoplasms with flattened nucleus in tube shaped pattern. pale vacules due to mucin, secretes sialomucin which is primarily for lubrication
- mixed: half moon shaped serous unti due to mix
What is saliva made of?
mainly composed of water, ions and proteins;
What are the ducts ofsalivary glands?
modifying the primary hypotonic saliva into an isotonic fluid by mediating several ionic changes between saliva and ductal cells
Interlobular ducts: pseudostratified colunar in deep section and stratified squamous towards opening of secretory duct. Immunohistology for cytokeratin, CAMP2, AE1/AE2, epitherlial membrane antigen. responsible for continuing the reabsorption of sodium and potassium secretion
- Intercalated ducts: homeostasis and replenishment, progenitor cells ,
- intralobulated: Majority of the ductal system in the major salivary glands, striated. regulating the secretion and reabsorption of electrolytes through a bidirectional transport between the lumen and the extracellular space
What do myoepithelial cells do?
glandular parenchyma, the contractile myoepithelial cells play an essential role in acinar salivary secretion. Lie in between the BM and basal plasma membrane. maintian duct patency (contractile proteins such as actin, caldesmon, calponin and smooth muscle actin)
How are salivary glands innervated?
early stages of development parasympathtic related for morphgensis
Neural growth factor (NGF) has been shown to be a key player in sympathetic neuron regulation in other systems and this pathway is expressed in human salivary glands
What is H and E staining?
Hematoxylin and Eosin staining is a histological stain for specimens.
-Hematoxylin is purple. it stains DNA, RNA (ribosomes), rER, and carbs in cartilage
Eosin stains pink, cystoplasm fillaments, membranes
Glabdular anatomy of the Parotid?
The parotid is composed of adipose, lymphoid, and subaceous glands, it has serous acini. largest of the major glands
Description: Pyrimidal shaped gland with the upper and lower lobe seperated by the facial nerve. It contians external carotid a., facial n. and retormandibular v.
Boundaries: Superior - Zygomatic Arch, Inferior - inferior boarder of the mandible, Posterior is Ex aud meatus and SCM, Anterior- Masseter. the stensons duct drains at the level of the upper 6s in BM. travels from deep lobe, anterior boarder to masseter, pierces buccinator and into the oral cavity
Nerve Supply: Sensory and autonomic. Sensory to capsule (auriculotemporal and greater auricular). paraympathetic from glossopharyngeal (otic ganglion). sympathetic from superior cervical ganglion.
Blood Supply: post auricular and superior temporal artery, retrmand vein
Lymphatics: preauricular and deep cervical nodes
Glandular anatomy of the submandibular?
Description: mixed gland (90% serous) with serous demilune acini. looks like elongated hook with a deep and superfical part
Location
Boundaries
Innervation
Blood supply
lymphatics
