title: The potential of the essential fatty acid-deficient hairless rat as a psoriasis screening model for topical anti-proliferative drugs.
abstract: The objective of this study was to establish essential fatty acid deficiency (EFAD) in hairless rats and investigate the potential of this model as a psoriasis screening model by testing the effects of calcipotriol and dithranol on differentiation and proliferation in the epidermis. Hairless rats were fed with a fat-free diet lacking linoleic acid. The EFAD condition was established within 8 weeks. In order to ensure that this condition had been established, several parameters were measured and observed, i.e. animal weight, water consumption, transepidermal water loss, clinical skin symptoms, histology of the epidermis and fatty acid analysis of serum and skin. Immediately after the EFAD condition had been established, the animals were treated with dithranol ointment or different concentrations of calcipotriol solution. A reduction in epidermal thickness of 15-20% was seen after the treatment with calcipotriol. Dithranol and its coal tar-containing vehicle also showed a reductive effect on epidermal thickness. EFAD hairless rats possess various histological changes resembling psoriasis. These histological changes normalise during treatment with anti-psoriatic drugs as calcipotriol, dithranol and coal tar. The results of the present study indicate that the EFAD rat may be a useful model for studies of anti-psoriatic drugs affecting cell proliferation.
authors.affiliation: Leo Pharmaceutical Products, Ballerup, Denmark.
authors.forename: Monika
authors.initials: M
authors.lastname: Jensen
authors.forename: Lotte
authors.initials: L
authors.lastname: Groth
authors.forename: Gunhild
authors.initials: G
authors.lastname: Hølmer
authors.forename: Harald S
authors.initials: HS
authors.lastname: Hansen
authors.forename: Ann
authors.initials: A
authors.lastname: Fullerton
mesh_terms: D000287:Administration, Topical; D000818:Animals; D000875:Anthralin / Q000494:pharmacology / Q000627:therapeutic use*; D000893:Anti-Inflammatory Agents / Q000494:pharmacology / Q000627:therapeutic use; D002117:Calcitriol / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use*; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D002455:Cell Division / Q000187:drug effects / Q000502:physiology; D003879:Dermatologic Agents / Q000494:pharmacology / Q000627:therapeutic use; D004195:Disease Models, Animal; D004353:Drug Evaluation, Preclinical / Q000379:methods; D000078404:Epidermal Cells; D004817:Epidermis / Q000187:drug effects / Q000473:pathology; D005228:Fatty Acids, Essential / Q000172:deficiency*; D005260:Female; D006131:Growth Inhibitors / Q000494:pharmacology*; D008297:Male; D011565:Psoriasis / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D051381:Rats; D011922:Rats, Mutant Strains
chemical_list: D000893:Anti-Inflammatory Agents; D003879:Dermatologic Agents; D005228:Fatty Acids, Essential; D006131:Growth Inhibitors; C055085:calcipotriene; D002117:Calcitriol; D000875:Anthralin