Vessels, Nerves, Pruritus

Question 1

T or F: Intraepidermal nerve fibers are increased in density in lesional atopic skin compared to normal skin or non-lesional atopic skin in both humans and dogs.

Answer 1

True

Question 2

Which body site has the greatest density of intraepidermal nerve fibers in healthy dogs?

a. chin
b. neck
c. calf
d. toe

according to de MM et. al. 2009

Answer 2

b. neck

Question 3

Name 3 body sites that tend to have a higher concentration of intraepidermal nerve fibers (IENFs) in people?

What about dogs?

What gradient do IENFs tend to follow?

Answer 3

finger pads, lips, genitalia

nasal planum

average IENF density decreases following a proximal to distal gradient along the limbs

Question 4

What is alloknesis?

Answer 4

Alloknesis is the itch or pruriceptive sensation or scratching behavior evoked by a stimulus that is normally non-pruriceptive

Question 5

Recognize 6 neural elongation factors secreted in the skin during allergic reactions

(probably too detailed to know all of them)

Answer 5

1. Nerve growth factor (NGF)
2. glial cell-line-derived neurotrophic factor (GDNF)
3. TNF-a
4. amphiregulin
5. artemin
6. IL-31

Question 6

What is the first cytokine gene transcribed as early as 1 hr after a single epicutaneous HDM challenge?

Answer 6

TNF-a

TNF-a is also a neural elongation factor.

Question 7

Theoretically, drugs like lokivetmab and oclacitinib could have an effect on decreasing intraepidermal nerves in the skin.

Why?

Answer 7

Because IL-31 is also a neural elongation factor