Allergic Rhinitis Intro Flashcards
describe the physiology of nasal mucosa
the nasal mucosa is rich in vascular tissue and controlled by the autonomic nervous system (both the sympathetic and parasympathetic)
line with mast cells that both contain and release histamine
sympathetic action on the nasal mucosa
sympathetics constricts arterioles, Reducing the mucosa thickness and widens the airway allowing for more air to enter
parasympathetic action on the nasal mucosa
increases mucosal thickness and increases stuffiness, runny nose is also experienced
what is the first line of immune defense in the nose?
the nasal muscle will cleans and conditions the inhaled air
how long does the antigen-antibody response take to initiate
seconds to minutes
how is the. antigen antibody response initiated
allergen interacts with IgE molecules bound to mast cells causing an immediate reaction and release of mediators
during the antigen antibody response mediators like histamine are released resulting in what?
vasodilation, increased vascular permeability and production of nasal secretions
how is itching produced in the antigen-antibody response of allergic rhinitis?
senstory nerve stimulation
how is sneezing produced in the antigen-antibody response of allergic rhinitis?
vagal stimulation pathways
describe the effect of the mediator histamine
stimulate irritant receptors, pruitis, vasular permeability, muscosal permeability and smooth muscle contraction
which mediator produces smooth muscle contraction, vascular permeability, mucus secretion, chemotaxis and neutrophil chemotaxis?
Leukotrienes
describe the effect of eosinophil chemotactic factor
influx of inflammatory cells
late phase reaction
- time after initial exposure
- is caused by?
- acute or chronic symptoms
- describe the effect on mucosa
4 to 8 hours after initial exposure
caused by cytokines primarily released by mast cells
persistent chronic symptoms
inflamed mucosa become hyper responsive
what are the results of a inflamed hyper responsive mucosa?
the mucosa reacts to nonspecific triggers
and has reactions to lower amount of the same antigen
why does clinical controversy exist in the treatment of allergic rhinitis?
avoidance steps are logical, but there is little existing evidence that environmental control measures provide clinical benefit, controls trails need to be performed