Nonrespiratory Functions of the Lungs: Khundmiri Flashcards
what are the other functions of the lungs besides gas exchange?
to maintain low fluid volume: lungs has its own mucosal associated tissues
Mucosa Associated Lymphoid Tissue (MALT)
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What are the Three tier defense mechanisms of the lung
Mucociliary clearance that moves inhales and trapped particles cephalad toward the mouth
Phagocytic and inflammatory cells that destroy inhaled substances
Specialized mucosal immune system
What is the function of the mucocialry and what are the three components?
to protect the lower respiratory system
Three major components (two fluid layers)
Sol – Periciliary Fluid
Gel Phase – Viscoelastic Mucus Layer
Cilia – Surface of the epithelial cells and embedded in the periciliary fluid
Describe the Periciliary Fluid
very important for the rhythmic beating of cilia
- epithelial sodium channels ENaC
- cystic fibrosis transmembrane receptors (cholride channel) - CFTR
- aquaporin (ADP) which are conducting water
sodium concentration allows what to occur
osmosis taking water from one portion of the cell to the other
If you add an inhibitor of sodium channel amiloride, what happens?
you are not transporting sodium inside the cells
given to HTN pts to inhibit sodium reabsorption in kidneys, thus lung volume should increase but that doesn’t happen because your system probably??????
you are building up osmolarity in the ???
increase ???
If you inhibit aquaporins
stops movement of water under physiological conditions because you don’t want to fill up the lungs with water
What is on top of the periciliary fluid?
-mucus layer
Functions to:
-to entrap inhaled substances
-Low viscosity and highly elastic
because of the glycoproteins that are present
make about 100 mL and are recyled out??
What are the four types of cells that make mucus?
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Goblet cells
secrete neutral or acidic glycoproteins
in pts who smoke or with chronic bronchitis produce large amount of mucus due to increased proliferation of goblet cells
Submucosal tracheobronchial glands
secrete acidic glycoproteins
they also contain enzyme with the function of killing bacteria
size and number increase in bronchitis
What are the differences between properties of submucosal glands serous and mucous cells?
granules are end close particles that contain digestive enzymes
mucus has no substance P
both are muscarinic
Clara cells
- Located in the epithelium if bronchioles
- Contribute to mucus secretion
- Secrete non-mucinous material containing carbohydrates and proteins
- Play important role in bronchial regeneration after injury: these cells can act as stem cells causing regeneration of the bronchial cells after injury; injury due to infection or trauma
What is the sputum clincally?
-Expectorated mucus
Serum proteins, lipids, electrolytes, Ca, DNA from degenerated white cells
Also contains extrabronchial secretions – nasal, oral, lingual, pharyngeal, and salivary secretions
Color of sputum correlates with presence of infection and how long it has remained in the lower respiratory tract
What causes the movement of mucus and clearing of??
cilia
What are cilia?
- originate from the basal body of epithelial cells
- are covered by an outcropping of the plasma membrane
- Ciliary movement is dependent upon ATP and also require Calcium and Magnesium
Describe cilia movement
- the cilia go into the mucus layer during forward movement
- present in the preciliar fluid during reverse beat
- nasopharynx beat in the direction to move mucus into the pharynx
- trachea propel mucus upward toward pharynx where it is swallowed