Respiratory Lecture Flashcards
Types of epithelia in respiratory system (6)
Stratified squamous PSCC with goblet cells PSCC sensory olfactory region PSCC of respiratory tree Simple cuboidal of alveolus Simple squamous of alveolus
What are the 3 regions the nasal cavity consists of
Sensory
- Olfactory
- Vomeronasal organ
Non-sensory
-Respiratory
What’s the primary function of the respiratory epithelium
Warm, clean, and humidify inspired incoming air
Olfactory system CNS or ANS
CNS sense of smell
What kind of neurons are in olfactory system
True neuron (exposed to outside world and vulnerable)
Bipolar neuron (true neuron, has axon and dendrite)
What types of receptors are in olfactory system
Odorant receptors on cilia
T/F Olfactory system is capable of neuron replacement
T
This is normal and happens when injured
Happens via basal cell mitosis (post natal neurogenesis) and development of new acon and dendrite.
When doing neurological testing for CN I use…
Food
NOT smelling salts
Where does olfactory neuron axon project
->Probelm?
Directly to CNS olfactory bulb
->Potential portal of infection to CNS
What are the 2 sensory systems present in canine?
Main olfactory system-in nasal cavoty
Vomeronasal system-opens into oral cavity
Where does the VNO system and main olfactory system connect
Connect with axon projections to olfactory bulb
What is the VNO system important for?
Mating and repro fxns
–>VNO Flehmen response
Sensory epithelium consists of (5)
Basal cells
Supporting cells
Bipolar olfactory sensory neurons
Olfactory axons in lamina propria
Bowman’s glands
Hyposmia and anosmia are a result from
Foreign bodies that damage nasal cavity mucosa…. can cause secondary infection
What are defensins?
- What fxns do they have
- Example
Small peptides produced by WBC and epithelial cells
Antimicrobial and immunomodulatory fxns
CBD 103 and pigmentation and feeding behavior
What is fxn of olfactory epithelium
Detect odorant materials
What are fxn of PSSC, Goblet cells, basal cells, supporting cells, olfactory neurons, axon bundles, Bowman glands
Protection
->Mucociliary blanket and defensins
What are some clinical implications of nasal cavity
Nasal mass will impact olfaction and respiration
What are the 3 layers of the trachea
Mucosa
Submcosa
Adventtia
What is the classification of trachea epithelium
PSCC with goblet cells
What are some physical structures of trachea
Hyaline cartilage ring
Trachealis muscle
Give breakdown of trachea
Bifurcates into 2 primary bronchi
Secondary bronchi (enters lung lobes)
Tertiary bronchi
Terminal bronchioles
T/F Trachea epithelium PSCC, gets “higher” as you work caudally down the conducting airway system
F
PSCC gets lower
As airway decreases in size what trends occur
Decrease in cartilage
Glands and epithelial height
Increase in smooth muscle
Distinguish what components of bronchial tree have cartilage and smooth muscle
Primary bronchi
-Cartilage plates
-Smooth muscle
(Primary component that maintains airway patency)
Secondary bronchi
- Cartilage plates
- Smooth muscle
Tertiary bronchi
- Cartilage plates
- Smooth muscle
Terminal bronchioles
- NO CARTILAGE
- Smooth muscle
What cells are in the respiratory epithelium
Ciliated cells Goblet cells Basal cells Brush cells DNES cells
What is the beginning of the respiratory portion of airway
Respiratory bronchioles
Respiratory bronchioles
- Epithelium
- Goblet ccells
- Alveoli
- Glands
Simple epithelium
Few goblet cells
Alveoli present in airway wall
No glands
In respiratory bronchioles, which extends farther, ciliated cells or secretory components?
Ciliated cells
What cells protect bronchiolar airway
Clara cells
-Columnar shape secretory cells
Is there gas exchange in terminal bronchiole?
Nope
-Dead air space
Is there gas exchange in respiratory bronchiole?
Yes
T/F Bronchial tree is conducting portion
T
What includes the conducting
portion?
Bronchial tree
- L and R primary bronchi
- Intrapulmonary bronchi
- Bronchioles
- Terminal bronchioles
What’s the difference btw intrapulmonary bronchi and primary bronchi
Primary bronchi=cartilage C rings
Intrapulmonary bronchi= Irregular hyaline cartilage
- Smooth muscle are in two distinct layers and spiral in opposite directions.
- Elastic fibers, radiate from adventitia to connect with elastic fibers arising from other parts of the bronchial tree (similar to terminal bronchioles)
What are the ranges of bronchiole epithelium
Ciliate simple columnar with occasional goblet cells in larger bronchioles to simple cuboidal (many with cilia) with occasional Clara cells and no goblet cells in smaller bronchioles
Termnal bronchioles are lined by…
-Lamina propria consists of…
Clara cells and cuboidal cells
Fibroelastic CT and 1-2 layers of smooth muscle cells
Elastic fibers similar to intrapulmonary bronchi
What cells produces surfactant
Type II cells…secrete surfactant on alveolar surface to reduce surface tension and keeps alveoli from inflating.
The respiratory portion of the respiratory system is composed of
Respiratory bronchioles
Alveolar ducts
Alveolar sacs
Alveoli
If alveoli are present, what occurs?
GAS EXCHANGE
So bronchioles=gas exchange
Terminal bronchioles=no gas exchange
Explain alveolar duct, alveolar sac, and atrium
Alveolar ducts do not have walls of their own and end as a blind outpouching made of alveoli. THIS IS ALVEOLAR SAC.
Alevolar sac open into common space and called ATRIUM
What are alveoli made of
Air sacs made of type I and type II (larger) pneumocytes
What is the region btw adjacent alveoli and what capillary bed is associated with it
Interalveolar septum
Continuous capillaries
What is the thinnest region of interalveolar septum where gas exchange can occur?
-What happens here
Blood-gas barrier.
-Type I pneumocytes in intimate contact with endothelial lining of capillary and basal laminae. Helps O2 (alveolar lumen) exchange with CO2 (blood)
Classify lung parenchyma
Simple squamous cuboidal
What cells can mitotically divide?
Type II pneumocytes and can differentiate into type I cels and re-establish air-blood barrier.
What makes up the majority of SA of the alveolus alveolar lining
Type I cells
If Type I cells are injured…
Type II cells can undergo mitosis and replace Type I cells and re-establish alveolar lining.
What is recruited to clear dead type I cells
-What are they called
Pulmonary MQ
-Heart failure cells because RBCs and hemosiderin content are called “gitter cells”
What is in the gas-blood barrier?
Surfactant Type I cells Fused basal lamina of Type I Basal lamina of endothelial cell Edothelial cell RBC
How can MQ move?
Pores of Kahn (intralevolar pore) in alveolar wall
Atelectasis
AKA
Collapsed lung
What are normal contents of pleural cavity
Scant amount of serous fluid (keeps frction low and surface tension high)
Air in pleural cavity
Pneumothorax
Blood in pleural cavity
Hemothorax
Pus in pleural cavoty
Pyrothroax
Where are tracheal collapse most seen?
Toy/miniature breeds
Cause of tracheal collapse
???
What’s critical management of tracheal collapse?
Weight management
What are defense mechanisms of repiratory tract
Nasal cacity
Mucociliary tract
Glandular and epithelial secretions of defensins antibmicrobial and antiviral proteins
Alveolar MQ
