title: Nickel-sulphate-induced contact dermatitis in the guinea pig maximization test: a dose-response study.
abstract: Nickel sulphate is a sensitizer in guinea pigs, but the frequency of sensitization varies from study to study. The dose-response relationship for NiSO4.6H2O was evaluated in the guinea pig maximization test in this study. 6 intradermal (0.01%-3.0% aq.) and 6 topical (0.25%-10.0% pet.) concentrations were chosen for induction and NiSO4.6H2O 1% pet. was used for challenge, based on the absence of skin irritation in a pilot study. Blind reading was performed. A logistic dose-response model was applied to the challenge results. At 48 h, a linear relationship was obtained between the intradermal induction dose (but not topical dose) and the response, resulting in a maximum sensitization rate of 40% after 3% i.d. The reactivity disappeared at re-challenge 1 week later. Following a booster closed patch on day 35, using NiSO4 10% pet., the animals were challenged with NiSO4 2% pet. and statistical analyses of 72-h readings revealed a non-linear dose-response relationship, giving a maximum response frequency of 40% after initial induction with NiSO4 3% i.d. and 2% topical.
authors.affiliation: Department of Dermato-venereology, Odense University Hospital, Denmark.
authors.forename: A E
authors.initials: AE
authors.lastname: Rohold
authors.forename: G D
authors.initials: GD
authors.lastname: Nielsen
authors.forename: K E
authors.initials: KE
authors.lastname: Andersen
mesh_terms: D000279:Administration, Cutaneous; D000818:Animals; D003877:Dermatitis, Contact / Q000209:etiology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D006168:Guinea Pigs; D007114:Immunization; D007271:Injections, Intradermal; D007509:Irritants / Q000008:administration & dosage; D009532:Nickel / Q000008:administration & dosage / Q000009:adverse effects*; D013997:Time Factors
chemical_list: D007509:Irritants; C029938:nickel sulfate; D009532:Nickel