title: Detection of kappa and delta opioid receptors in skin--outside the nervous system.
abstract: Opioid receptors (OR) are widely expressed in the central nervous system (CNS). Opioid antinociception might be initiated by activation of OR outside the CNS, indicating targeting of peripheral OR could be useful in the treatment of chronic pain. This study was designed to detect OR in skin tissues of healthy volunteers at both mRNA and protein levels. Skin samples from 10 healthy individuals were investigated. Total isolated RNAs were reverse transcribed, amplified and quantified by real-time PCR. Tissue and skin fibroblast OR protein was detected by immunohistochemistry, Western blot, and immunofluorescence. All skin tissue samples expressed delta- (DOR) and kappa-OR (KOR) mRNAs. Using immunohistochemistry, DOR and KOR were localized in skin fibroblast-like and mononuclear cells. Skin fibroblasts in culture expressed DOR and KOR mRNA. Using immunofluorescence, both DOR and KOR proteins were expressed predominantly on the cell membrane with minor staining in the cytoplasm. We suggest that enhanced expression of DOR and KOR in skin justifies the exploration of selective novel delta and kappa agonists for local pain treatment.
authors.affiliation: Center of Experimental Rheumatology, Department of Rheumatology, Institute of Physical Medicine, University Hospital, Gloriastrasse 25, Zurich, Switzerland.
authors.forename: Souzan
authors.initials: S
authors.lastname: Salemi
authors.forename: André
authors.initials: A
authors.lastname: Aeschlimann
authors.forename: Natasa
authors.initials: N
authors.lastname: Reisch
authors.forename: Astrid
authors.initials: A
authors.lastname: Jüngel
authors.forename: Renate E
authors.initials: RE
authors.lastname: Gay
authors.forename: Frank L
authors.initials: FL
authors.lastname: Heppner
authors.forename: Beat A
authors.initials: BA
authors.lastname: Michel
authors.forename: Steffen
authors.initials: S
authors.lastname: Gay
authors.forename: Haiko
authors.initials: H
authors.lastname: Sprott
mesh_terms: D000328:Adult; D002478:Cells, Cultured; D002490:Central Nervous System / Q000378:metabolism; D005260:Female; D005347:Fibroblasts / Q000378:metabolism*; D006801:Humans; D017465:Receptors, Opioid, delta / Q000378:metabolism*; D017473:Receptors, Opioid, kappa / Q000378:metabolism*; D012867:Skin / Q000378:metabolism*; D014018:Tissue Distribution
chemical_list: D017465:Receptors, Opioid, delta; D017473:Receptors, Opioid, kappa