Lec 8/9-3 - Somatosensory System & Pain Flashcards
hair receptors are considered to e this type of receptor
mechanoreceptor
hair being bent causes mechanoreceptors to change blank and let sodium in and generate blank via voltage gated channels
conformation, an action potential
for fine tactile sensation from touch and light pressure
meissner corpuscles
meissners corpuscle has blank adaptation
rapid
for touch but adapt slowly
merkel endings
meissners are located here
epithelium
merkels are located here
basal epidermis
these are sensitive to vibration
pacinian
pacinian adapt blank
fast
pacinian are located here
ct and subcutaneous throughout entire body
pacinian corpuscles are best for the first signs of blank
neuropathy
most common receptor in the mouth
ruffini
ruffini is located here
subcutaneous and ct
ruffini adapts blank
slow
c tactile afferents are myelinated/unmyelinated and involved in blank
unmyelinated, pleasure/stroking
location where a change in the stimulus leads to a change in the firing of a cell
receptive fields
receptive field size of fingers
tiny
some receptive fields are small due to blank
inhibitory circuits
more convergence leads to a blank receptive field
larger
blank organization tells us where things are and where they are not
center surround
most somatosensory information is from this neuron in the column
4
blank can modify activity of cortical somatosensory neurons
attention
response of tactile sensation is filtered by blank
thalamus
periodontal ligaments contain these
free nerve endings, ruffini mechanoreceptors
teeth contain blank
pain fibers
how many types of dental sensory fibers
6
these provide information about tooth loading and direction the teeth are being pushed
periodontal ruffini endings
periodontal ruffini endings die when blank
tooth is pulled and implant is placed
detection and localization of a stimulated pain receptor
nociceptor
this involves the emotional and arousal aspects of such stimulation
pain
pain and temp are always translated along blank pathways
the same
thermoreceptors can transmit information of blank or blank temp ranges
non noxious, noxious
menthol activates these thermoreceptors
cold
capsaicin in peppers activate these thermoreceptors
capsaicin
capsaicin works by depleting this transmitter
substance p
ibuprofen is blank selective compared to aspirin
more
both aspirin and ibuprofen block blank
cox 2
aspirin is a blank which selectively blocks pain and doesnt affect other senses
analgesic
anesthetics block blank so other senses are also affected
nonselectively
this activates mast cells, macrophages, and neutrophils
substance p
cgrp and subtance p cause blank which causes edema and more pain
vasodilation/plasma leakage
increased sensitivity to pain
hyperalgesia
pain due to a simulus that does not normally provoke pain
allodynia
painful inflammatory infection of the pulp
pulpitis
immune cells are the major source of the peripheral blank
opioid
endorphins are aka
endogenous morphine
opioid receptors have effects by changing second messengers like blank
cAMP
peripheral opioid receptors lead to less activation of these channels which decreases pain
calcium, voltage gated sodium
pain fibers use a blank kind of sodium channel compared to non pain fibers
different
can develop after traumatic damage to peripheral nerve and one mechanism is upregulation of sodium channels which leads to more pain
causalgia
blank projections in spinal cord control how much pain reaches consciousness
descending
gate control theory can act by this mechanism to reduce pain transmission by releasing endorphin
presynaptic
gate control theory can work by this mechanism which increases potassium channel activity so the cells are less excitable
postsynaptic
tens activates this size of axons wherever pain is to inhibit the pain
large
wide dynamic range of dorsal horn projection cells means that it responds to these inputs`
touch, pain
repeated or extremely intense painful stimuli can make cns neurons abnormally prone to firing and the synapse becomes stronger
central sensitization
one mechanism of central sensitization is from extreme activation of blank receptors
nmda glutamate receptors
pain that does not have a visible cause like phantom limb
neuropathic pain
fast pain is done by the blank cortex and localizes pain but doesnt tell about the magnitude of the pain
somatosensory
slow pain is the emotional response to pain and is done here
anterior cingulate cortex
cannabinoids work via blank receptors and are blank because they work backward and act on the presynaptic cell
g protein cannabinoid, retrograde
cannibinoids inhibit targest by reducing this channel activity and activating blank channel activity
calcium, potassium
cannabinoids reduce pain like blank
opioids
two types of itch
chemical, mechanical
chemical itch is mediated by blank
c fibers
mechanical itch is mediated by blank fibers
c and a
