Pain/Fine Touch Flashcards
List the senses (ways body perceives external stimulus)
- balance
- thermoreception
- pain
- propioreception (sense of body position at any time)
A change in the electrical potential of a receptor is ______________________
Receptor potential
Describe an adequate stimulus
Physical energy a receptor is tuned to respond to
What is proportional to stimulus intensity?
Receptor potential amplitude and action potential frequency
When a receptor has a high rate of response followed by a lower response rate with continued stimulus it is called:
Adaptation
List the 3 classes of receptors
Exteroreceptors
Propioceptors
Interoceptors
Which type of recpetor detects stimuli from inside body? Some receptors are pH, O2, level in arterial blood, CO2 concentration, etc
Interoceptor
Describe propioceptors location and sensitivity
Location: skeletal muscles/tendons, ligaments
Sensitive: muscle stretch, muscle tone, and angle of joints
Which receptors detect stimuli near outer surface of body and include skin (cold, warm, touch, pressure, vibration)?
Exteroceptors
List examples of exteroceptors
- mechanoreceptor
- thermoreceptors
- nociceptors = pain
- chemoreceptor = taste/smell
The receptor types for temperature are?
Cold - bulbs of Krause
Warm - Ruffini organs
Which fibers are the bare or encapsulated nerve endings associated with?
A-delta and C fibers
What is the Channel associated with temperature?
Transient Receptor Potential channel
What is special to vampire bats that alllow them to detect infrared radiation?
3 nasal pits
How are the 2 TRPV1 receptors activated in vampire bats?
Long form at heat - 109 F
Short form at cold 86 F
Which TRPV1 detects infrared in vampire bats?
Short form
Which sensory fibers origin innervated the pit membrane in rattlesnakes for infrared detection?
Trigeminal ganglion
Which mechanoreceptors detect pressure?
Merkel’s disk, Tactile disk, Ruffini’s corpuscle
List the 2 characteristics of stimulus detection
- tactile location: id where stimulus originates
- tactile discrimination: 2 pt discrimination
Skin areas innervated by spinal nerves are called:
Dermatomes
Which receptors detect pain?
Nociceptors
What can pain elicit ?
a protective or aversive reaction to remove the organism from the stimulus
List some stimuli that excite nociceptors
- mechanical stress
- extreme temps
- ischemia
- inflammatory chemicals (H+, K+, histamines, Pgs, etc)
__________ fibers transmit fast pain
A-delta
__________ fibers transmit slow pain
C fibers
Describe pain transmission
Cell body in dorsal root ganglion
What is the1st synaptic relay for pain inflammatory from periphery?
Dorsal horn of spinal cord
Cells of nociceptors are in the dorsal root ganglion and terminate as?
Free endings in peripheral tissues
What type of analgesia system is thought to exist in the brain?
Intrinsic/endogenous
What type of analgesia system is thought to exist in the brain?
Intrinsic/edogenous
What area needs to be stimulated in the midbrain to produce selective suppression of pain?
PAG -periaqueductal gray matter
What does PAG stimulation inhibit?
Dorsal horn pain transmission cells
What does the PAG and opioids activate in the Rostral ventromedial medulla (RVM)?
The nucleus raphe magnus (NRM)
PAG neurons release __________ onto NRM neurons
enkephalin
Serotonin is released by __________ neurons onto dorsal cord neurons
NRM
In the __________________, substance P is released by nociceptor afferent onto pain transmission cells
Spinal cord dorsal horn
What inhibits release of substance P in the dorsal horn?
Opiates
What channels are closed in an opioid moa?
Calcium
What ions exit the cell in an opioid moa, thus hyperpolarizing it?
Potassium
List where you can find opioid receptors through the body
- brain
- brainstem
- spinal cord
- peripheral neurons
- intestines
If the brain stem is affected by opioid activity, what can be affected?
Respiration
Why may constipation be a side effect of opioid medications?
Because receptors are expressed in neurons regulating peristalsis
