PAIN PATHWAYS Flashcards
What is pain?
- perception/ feeling of irritation or painful sensation
- associated with actual or potential tissue damage
- can occur when no cause
- can persist after injure is healed
- consequence of brain or nerve injury
What is nociception
sensory process that provides signals to trigger pain
what is the most frequent type of pain
musculoskeletal (back pain)/rhematic pain (RA)
anti-nocicpetion?
sensory process that provides signals to relive pain
What is physiological pain?
- warning device to damaging stimuli
- activation of nociceptors/ion channel complexes
What receptors are associated with acute chemical pain?
TRPV1 & P2X3
What receptors are associated with heat?
TRPV1 & TRPV2
What receptors are for mechanical pain?
ion channels
What is allodynia?
pain evokes by non noxious stimuli
What is hyperalgesia?
pain evoked by noxious stimuli
How is pain transmitted?
afferent neurones are stimulated with then leads to pain stimulation sent to the spinal cord which is then sent to the thalamus (via spinothalamic tract), moving to the sensory motor cortex and then pain is felt
What are the mediators generated by tissue damage
- protons
- nitric oxide
- ATP & adenosine
- bradykinin
- inflammatory mediators e.g. prostoglandins, cytokines, histamine
- 5-HT
With what mediators are nociceptors activated?
bradykinin, 5-HT, histamine, prostaglandins via seperate receptor mechanisms
What are the 3 types of afferent neurones?
A delta fibres
C fibres
A beta fibres
What are A delta fibres for
- they are myelinated fibres for transmission of sharp acute sensations
- mechanoreceptor/nocicpetor
