title: Allergen-induced histamine release in intact human skin in vivo assessed by skin microdialysis technique: characterization of factors influencing histamine releasability.
abstract: BACKGROUND
  The purposes of the study were to characterize allergen-induced histamine release in intact human skin in vivo by using a novel microdialysis technique and to study covariates influencing histamine releasability.
  
  
  METHODS
  Hollow microdialysis fibers were inserted into the upper dermis in 15 timothy-sensitivity subjects. Up to 12 fibers were inserted in each subject. Each fiber was perfused with Krebs-Ringer's solution at a rate of 3.0 microliters/min. Three to four serial dilutions of allergen were applied to the skin by intracutaneous injections or skin prick test above individual fibers. Samples were collected in two 2-minute fractions before skin challenge and in 10 consecutive samples for 20 minutes after skin challenge. Histamine was assayed spectrofluorometrically.
  
  
  RESULTS
  A significant dose-response relationship for histamine release was demonstrated with intracutaneous tests and skin prick tests. The time to reach peak histamine release after an intracutaneous test was 4 to 8 minutes, compared with 12 to 14 minutes for a skin prick test. Histamine release correlated significantly with wheal size. Intrasubject coefficient of variation on histamine release was about 20%. A substantial intersubject variation in histamine releasability was observed. Seventy to seventy-five percent of the variation could be accounted for by a combination of gender, total and allergen-specific IgE, and an in vitro basophil histamine release test.
  
  
  CONCLUSIONS
  Using a skin microdialysis technique, we have described in detail histamine release in intact human skin by allergen. The microdialysis method proved to be a reproducible technique for monitoring histamine release in allergic skin reactions and for studying histamine releasability of skin mast cells in vivo.
authors.affiliation: Department of Dermatology, Bispebjerg Hospital, Copenhagen NV, Denmark.
authors.forename: L J
authors.initials: LJ
authors.lastname: Petersen
authors.forename: H
authors.initials: H
authors.lastname: Mosbech
authors.forename: P S
authors.initials: PS
authors.lastname: Skov
mesh_terms: D000328:Adult; D000485:Allergens / Q000008:administration & dosage / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006636:Histamine Release / Q000276:immunology*; D006801:Humans; D007271:Injections, Intradermal; D007700:Kinetics; D008297:Male; D017551:Microdialysis / Q000379:methods; D015203:Reproducibility of Results; D012867:Skin / Q000276:immunology* / Q000378:metabolism; D012882:Skin Tests
chemical_list: D000485:Allergens