Quantification of cutaneous sensory nerves and their substance P content in psoriasis.
The aim of the present study was to extend our previous hypothesis that the inflammatory reaction in psoriasis is neurogenic, and that substance P mediates the inflammation. For this purpose, the pattern of neurofilament-positive sensory nerve fibers was studied and the lengths and substance P content of these fibers measured morphometrically in dermal and epidermal compartments of the psoriatic lesion, psoriatic but lesion-free skin, and control skin. The epidermis and dermis of the psoriatic lesions were significantly more densely innervated with neurofilament-positive fibers than either lesion-free psoriatic or control skin. Although substance P is known to be rapidly degraded in tissues, and its actual concentrations in the sections were unknown, there was an increase in substance P containing nerves in the psoriatic lesion, the increase being significant in the epidermal nerve fibers. No significant differences in the measured parameters were obtained between lesion-free psoriatic and control skin. These results indicate that there is an altered pattern of sensory nerves in a psoriatic plaque and that substance P may be an important mediator in the inflammatory processes that contribute either to the initiation or maintenance of a psoriatic lesion.
Naukkarinen
A
A
Psoriasis Research Institute, Palo Alto, California.
Nickoloff
B J
BJ
Farber
E M
EM
D000328:Adult; D001706:Biopsy; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008875:Middle Aged; D009475:Neurons, Afferent / Q000032:analysis* / Q000166:cytology / Q000473:pathology; D011565:Psoriasis / Q000378:metabolism / Q000473:pathology*; D012867:Skin / Q000294:innervation*; D013373:Substance P / Q000032:analysis* / Q000378:metabolism
D013373:Substance P