๐ ็ธฝ็ฎ้ ๏ฝ ๐ ่ฑๆๅๆ๏ผๆฌ็ฏ๏ผ ๏ฝ ๐ ๅฎๆด็ฟป่ญฏ ๏ฝ โญ ็ฒพ่ฏ็ญ่จ
Introduction
Gil Yosipovitch and Brian Kim Cutaneous Neurophysiology
Key features
ยAt least three subsets of pruriceptive C neurons exist that respond to histamine or other pruritogens and then activate distinct spinothalamic and spinoparabrachial tract neurons
ยPeripheral itch mediators include histamine, proteases, and multiple interleukins
ยCentral itch mediators include opioids, gastrin-releasing peptide, and B-type natriuretic peptide
ยThere is an overlap between chronic itch and chronic pain, including activation of multiple brain areas and associated neuromediators and receptors, e.g. nerve growth factor, neurotrophin 4, transient receptor potential (TRP) channels
ยCross-talk between cutaneous nerve fibers and the stratum corneum is a possible mechanism for the pruritus associated with impaired barrier function (e.g. xerosis, atopic dermatitis)
ยTherapies with topical and systemic drugs that reduce itch sensi- tization by counteracting the responsible mediators represent promising treatment strategies