title: Topical and systemic effects of retinoids on horn-filled utriculus size in the rhino mouse. A model to quantify "antikeratinizing" effects of retinoids.
abstract: A method was developed to quantify the "antikeratinizing" effects of various retinoids (all-trans-retinoic acid, 13-cis-retinoic acid, motretinide, etretinate) in rhino mouse skin, which contains many keratinized pilosebaceous structures or horn-filled utriculi. Mean utriculus diameters in whole mount epidermis were determined and dose-response relationships were constructed after topical or oral administration of test retinoids. All-trans-retinoic acid was 3.7x, 12.5x, and 50x more potent than 13-cis-retinoic acid, etretinate, and motretinide, respectively, after topical administration. Administered orally, all-trans-retinoic acid was 2.3x more potent than 13-cis-retinoic acid. At 5 mg/kg, each retinoid produced a significant reduction in utriculus size. The rhino mouse model represents a novel and useful assay to quantify antikeratinizing activity and potency differences of biologically active retinoids.
mesh_terms: D000284:Administration, Oral; D000287:Administration, Topical; D000818:Animals; D002454:Cell Differentiation / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D000078404:Epidermal Cells; D004817:Epidermis / Q000187:drug effects*; D007633:Keratins / Q000037:antagonists & inhibitors*; D051379:Mice; D008812:Mice, Hairless; D012176:Retinoids / Q000494:pharmacology*; D013997:Time Factors
chemical_list: D012176:Retinoids; D007633:Keratins