Respiratory Epithelium Flashcards
1
Q
conducting epithelium
-where is it found
A
pseuodostratified, ciliated, columnar, with gobs
- nasal cavity
- larynx, trachea
- bronchi
- intrapulmonary bronchi
- however, transitions to non-ciliated cuboidal epithelium in deeper passageways
- NO gas exchange occurs here!!
- enteroendocrine cells, kulchitsky cells are present here
2
Q
what cell types do you find in gas exchange epithelium?
A
type 1 and 2 alveolar (pneumocytes) cells
3
Q
olfacotry epithelium is composed of
A
- supporting cells (these cells reach the surface and have non-motile cilia
- olfactory cells (bipolar neurons): these have dendrites which reach up to the surface and are what transmit the smell signal, axons extend into the lamina propria and are surroudned by schwann cells
- basal cells (stem cells)
- bowmans glands under epithelium
4
Q
kulchitsky cells
A
- enteroendocrine cells foundin the resp tract
- small granule cells
- release catecholamine, serotonin, calcitonin, etc
5
Q
respiratory problems in CF
A
- defective chloride channel makes the mucous very concentrated
- due to the lack of eflux of Cl, a lot of Na comes into the cell in order to maintain the gradient and water rushes into the cells along with the sodium, leaving the mucous remining in the lumen very thick (viscous)
6
Q
trachea is composed of (from lumen to outer layer)
A
- respiratory eptihelium
- lamina propria
- longitudinal elastic fibers
- submucosal mixed seromucous glands (lots of glands)
- hyaline cartilage
- adventitia
- there is also a muscle on one side called the trachealis muscle which can stretch when food is going down the esophagus or narrow when coughing
- THERE IS NO MUSCULARIS MUCOSAE
7
Q
bronchiole
A
- no mucosal glands
- no cartilage
- few goblet cells
- many club (clara) cells
- mostly simple cuboidal cells
8
Q
club cells
A
- non ciliated
- produce surfractant components
- repair (stem cells)
- protect against inflammation and oxidative stress
- this is not the main surfactant that is going to keep the lung open
9
Q
respiratory bronchiole
A
- bronchiole with alveoli (at least one)
- capable of gas exchange in alveoli
10
Q
surfactant
A
- surface active agent
- dipalmitoylphosphatidylcholine
- proteins
- reduces surface tension in order to make lungs more compliant and prevent atelectasis (collapse)
11
Q
respiratory distress syndrome
A
- surfactant is not produced in large volumes until about 6 months of developmetn
- may occur with premeys that are incapable or inefficient at producing surfactant
- administered corticosteroid to increase production
12
Q
cells of the alveoli
A
- type 1 and 2 pneumocytes
- macrophage
13
Q
type 1 pneumocyte
A
- thin nuclei,
- creates 90% of the surface area for gas exchange
- has a very thin cytoplasm that surround the endothelial cells of capalaries that are carrying blood to the lungs
- not capable of cell division, requires proliferation of type 2
- very squamous
14
Q
type 2 pneumocyte
A
- contain lamellar bodies that are represented as clear areas within the cell. lipid rich sotred surfactant
- round nuclei
- produce surfactant
- progenitors for type 1 pneumocytes
15
Q
macrophage
A
-known as a dust cell in the lung
