Scale prophylaxis. A new antiparakeratotic assay

Abstract

This article describes a new animal model for the evaluation of drugs that may prevent the development of parakeratosis. The advantages of this model are simplicity, economy, and the opportunity to observe the possible occurrence of acute systemic toxic reactions. High-boiling coal tar acids (phenols), vitamin A (retinyl acetate), and hydrocortisone butyrate (Locoid) were assayed. Only tar phenols consistently prevented scale development. Vitamin A was not properly screened because of toxic effects that resulted in premature termination of the experiment.

The mouse epidermis as a model in skin pharmacology: influence of age and sex on epidermal metabolic reactions and their circadian rhythms

“…Drugs for topical or systemic treatment of skin diseases are tested in vitro using keratinocyte cultures or in vivo in human beings or in laboratory animals (Wrench, 1981;Marks et al, 1983;Zmolek et al, 1983;Lowe et al, 1984;van den Hoven et al, 1987;Hofbauer et al, 1988;Lubach & Kietzmann, 1988a,b;Kietzmann & Lubach, 1989). Because of differences in the histology and metabolism of the epidermis of different skin regions, the compatibility of results is often poor.…”

“…Drugs for use in dermatology are frequently tested in the mouse tail assay (Spearman, 1964). Histologically, the tail epidermis differs from that of other body regions (Wrench, 1981;Militzer, 1982). The tail epidermis shows orthokeratotic and parakeratotic regions.…”