A novel in vivo model in guinea pigs for dry skin syndrome.
BACKGROUND/AIMS: The lack of a suitable, validated animal model for the comparison of the pharmacological effectiveness of known and potential moisturizers in the treatment of "dry skin syndrome" led us to develop such an in vivo model. METHODS: "Dry skin syndrome" was induced in guinea pigs by daily application of 2% sodium lauryl sulphate (SLS) in deionized water on one of the two shaved flanks for three consecutive days. After ascertaining skin dryness, that side was treated with an agent for 6 days. The in vivo humectant effect was measured by a Corneometer CM 825(R), erythema was measured by a Mexameter MX 16(R). In some cases histological studies were carried out. RESULTS: The treatment with the 2% SLS led to a consistent "dry skin syndrome" for 2 weeks. Glycerol, Vaseline, urea and ammonium lactate treatments validated the model, since the Corneometer CM 825(R) readings of the treated dry side was equal to that of the control untreated side after 1 week of treatment. Mexameter MX 16(R) measurements showed abolishment of the erythema by glycerol only. Histological study showed that SLS treatment creates acanthosis that is partially reversed by Vaseline and fully reversed by glycerol treatment. CONCLUSION: The guinea pig dry skin model is a relevant model of the human "dry skin syndrome". The instrumental results combined with the histological findings indicate that erythema measurements are relevant for the determination of curative effect.
Sagiv
Assaf Eliezer
AE
Unit of Cell Pharmacology, School of Pharmacy, Faculty of Medicine, Hebrew University and Department of Dermatology, Hadassah University Medical Hospital, Jerusalem, Israel.
Ingber
Arieh
A
Dikstein
Shabtay
S