Physiology 8: Pain and Thermosensation

Question 1

pain in the viscera often refers to..

Answer 1

a somatic structure

Question 2

nociceptors are what type of neuron?

Answer 2

primary sensory afferents

Question 3

nociceptors are __ order neurons

Answer 3

first

Question 4

how do nociceptors relay information to second order neurons?

Answer 4

by chemical synaptic transmission using neurotransmitters

Question 5

where does transduction begin?

Answer 5

free nerve endings

Question 6

name the 2 types of fibres that can be nociceptors?

Answer 6

A-delta fibres

C fibres

Question 7

which type of nociceptor fibre is myelinated?

Answer 7

A-delta

Question 8

which type of nociceptor fibre is for slow pain?

Answer 8

C fibre

Question 9

which type of nociceptor fibre is for mechanical stimuli? ooes this fibre work fast or slow?

Answer 9

A-delta fibre

fast

Question 10

how do thermal stimuli project to the CNS?

Answer 10

via depolarisation from an Na/Ca influx causing an AP

Question 11

how do chemical stimuli cause a response?

Answer 11

chemicals activate specific receptors to cause a response

Question 12

what neuro tracts are involved in the pain response?

Answer 12

spinothalamic

spinoreticular

Question 13

some C fibres transmit pain info to the CNS via release of….

Answer 13

glutamate and peptides

Question 14

some C fibres project pain by releasing…

Answer 14

pro-inflam mediators eg CGRP and substance P

Question 15

what does substance P cause?

Answer 15

vasodilation
leakage of plasma proteins
histamine release
= NEUROGENIC INFLAM

Question 16

what does CGRP do?

Answer 16

causes vasodilation

Question 17

main symptoms of neurogenic inflam?

Answer 17

primary and secondary hyperalgesia and allodynia

Question 18

peptides cause a fast EPSP T or F

Answer 18

F, cause a slow, prolonged EPSP

Question 19

primary afferent cell bodies are located where?

Answer 19

dorsal root ganglia

Question 20

where do the axons of primary afferents terminate?

Answer 20

dorsal horn of spinal cord

Question 21

cells that receive input from alpha-beta fibres will provide sensory info of what function only?

Answer 21

proprioception

Question 22

what types of neurones receive input from all 3 types of fibre?

Answer 22

wide dynamic range neurons

Question 23

visceral afferents from nociceptors follow what pathway before entering the dorsal horn?

Answer 23

sympathetic

Question 24

why do you get referred pain

Answer 24

some visceral and skin afferents converge on the same neurons at a given area and the brain thinks the visceral pain is coming from the skin afferent

Question 25

heart dermatomes for referred pain?

Answer 25

T1-5

Question 26

gallbladder dermatomes for referred pain?

Answer 26

C4

Question 27

do nociceptive tracts use the anterolateral or ventromedial system?

Answer 27

anterolateral

Question 28

which nociceptive tract is responsible for C fibres ie slow pain?

Answer 28

SRT

spinoreticular

Question 29

spinothalamic tract is responsible for __ pain

Answer 29

STT (spinothalamic)

Question 30

which tract is for pain perception?

Answer 30

STT

Question 31

SRT is for which type of pain?

Answer 31

autonomic pain, arousal, emotional responses