BAB 2b Flashcards
What type of nerves are nociceptors? What type are not?
a. free nerve endings, myelinated or unmyelinated.
b. encapsulated,-eg Pacinian, Ruffini, Meissner and Merkel
What type of axons does a pinch travel thru? Burning heat?
a. A-delta axons
b. A-delta and C axons
* you can have polymodal effects, too
What do nociceptor endings have? Which is the most common?
Transient Receptor Potential/Vanilloid Receptors.
TRPV1 is most common: heat acid, alcohol and capsaicin
What are some chemical stimulators of pain?
Bradykinin, ATP, prostaglandins, cytokines, histamine, K+, Staph aureus etc, etc.
What does substance P and the NB Axons reflux do?
increases intensity and area involved in the pain stimulus.
What are some surgical sites to remedy pain?
a. DRG lateral aspect
b. off center in spinal column
c. ALS
What congenital condition can lead to an absence of pain?
mutations that result in elimination of small-diameter axons
What type of axons carries “Ouch!” pain as compared to “Groan!” pain? Which is more associated with memory?
Ouch! = A-delta, myelinated and fast (5-30m/s)
Groan! = C fibers, unmyelinated, slow (0.5-2m/s). MORE ASSOCIATED WITH MEMORY.
What is the relationship between the Neospinothalamic tract and the Paleospinothalamic tract?
The Neo has a negative feedback mechanism on the Paleo, -eg rubbing a stubbed toe. Conversely, damage to the Neo tract can cause NEUROPATHIC PAIN, -eg DMII
What is the GATE-CONTROL THEORY?
Non-pain fibers can block pain.
What is the interneuron transmitter for pain mediation?
enkephalin
How do endogenous opioids act?
a. inhibit presynaptic Ca channel to reduce NT release
b. activate K channels (GIRKs) which hyperpolarize the cell
When is the endogenous opioid system working?
always, but it’s a sinusoidal wave and least effective right before sleep.
What are the following: Affect, Mood, Affective (mood) disorder?
a. Affect: the weather
b. Mood: the climate
c. Affective disorder: maladaptive exaggeration or distortion of emotions.
What is the limbic system?
The center is the amygdala, the processor of emotion. Receives input from thalamus and sensory cortices.
