Somatosensation

Question 1

What temperatures do cold receptors work under?

Answer 1

5-35˚ C

Question 2

What temperatures do hot receptors work under?

Answer 2

30-45˚ C

Question 3

Nociceptors open to what types of stimuli?

Answer 3

heat > 45˚ C and capsaicin

Question 4

Sensitization of what type of receptors causes hyperalgesia?

Answer 4

nociceptors

Question 5

NSAIDs focus to reduce the release of what type of molecule?

Answer 5

prostaglandins

Question 6

What are TRP proteins?

Answer 6

non-specific cation channels that open to many different forms of stimuli

Question 7

What is an itch?

Answer 7

a perception that isn’t present

Question 8

3 types of pain

Answer 8

1. acute nociceptive
2. inflammatory
3. neuropathic

Question 9

Two types of nociceptive pain

Answer 9

• fast, sharp pain

- slow, non-well localized pain (C fibers)

Question 10

Neuropathic pain pathophys

Answer 10

complex reorganization of neural pathways, pain even in absence of stimulus

Question 11

Neuropathic pain: CNS or PNS?

Answer 11

both CNS and PNS

Question 12

What is the cause of referred pain?

Answer 12

breakdown in parallel processing

Question 13

Draw out the gate theory of pain

Answer 13

1˚ afferent breaks into two axonal portions:

• excitatory synapse onto 2˚ afferent
• inhibitory synapse onto inhibitory gate cell
• inhibitory gate cell constitutively inhibits 2˚ afferent
• 1˚ afferent stimulation excites 2˚ afferent and inhibits inhibitory gate cell
• opiates increase inhibitory gate cell secretions