10 0 - EleA@UniSA - Università degli Studi di Salerno

FIGURE 1.26-TRP Receptors Family: Temperature-Range Of Activation, Agonists And
Tissue Distibution
It has been shown that TRP channels are involved in trigeminal chemosensory.
Trigeminal somatosensory system play a key role in chemosensation, Sensory
ending of trigeminal nerves are located all around the face, or in mucous
membrane of nasal and oral cavities and are activated by physical stimuli (such
as temperature) or chemical stimuli and evoked sensation of touch or pain.
Protective responses evoked by trigeminal stimulation include salivation,
tearing, coughing, respiratory depression, and sneezing .Moreover, pungent
irritation or burning pain is a very common side effect of drugs applied topically
to the skin.
Chemical signaling of taste and smell involves the following mechanism; binding
of the chemical agent to the receptor activates a protein that initiates a
transduction cascade. In contrast, activation of somatosensory afferents by
chemicals involves the direct gating of an ion channel by the chemical stimulus
and is called ionotropic transduction. In either case, the chemical signal leads to
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