1 Physiology of Pain Flashcards
What is pain
sensory and emotional experience associated with tissue damage
Nociception versus pain?
Nociception = ability to feel pain (stimulation of nociceptor))
can experience physical trauma and not feel pain; can feel pain without physical evidence of ongoing nociception
4 parts of nociception
Transduction, transmission, modulation, perception
acute versus chronic pain
“good” pain = acute pain; associated w/ damage, gets better as tissue gets normal
chronic (unremitting) pain = chronic inflammation, is bad
When do you go from acute to chronic?
past 3-6 months
How does sensitization contribute to chronic pain?
Sensitization mechanisms are stressed and lead to greater pain scenarios.
The longer you have pain, the harder it is to fix pain syndrome.
Which kind of pain is associated with tissue destruction?
Slow pain
chemicals that cause slow pain?
bradykinin, serotonin, histamine, potassium ions, acids, acetylcholine, proteolytic enzymes
How much do pain receptors adapt?
Little/not at all.
Except pain fiber excitation can become progressively greater, called hyperalgesia
pathways for pain transference to CNS?
fast/sharp pain pathway
slow/chronic pain pathway
which pathway do fast pain fibers travel through?
Neospinothalamic tract from DRG to thalamus, cortex
Which pathways do slow pain fibers travel though?
paleospinothalamic tract
What are causes of true visceral pain?
tissue ischemia chemical damage smooth muscle spasm distension of hollow viscous Ligamentous stretching
Where does pain go when it enters the spinal cord?
One branch to DRG at that level, one branch up, one branch down
How does rubbing a boo-boo make it feel better?
stimulation of Abeta fibers is faster than pain signals; depresses transmission
