title: Guinea pig ear as a new model for in vivo percutaneous absorption.
abstract: A new animal model for in vivo percutaneous absorption utilizing the hairless, relatively thick skin of the guinea pig ear is proposed. Topical absorption studies were carried out with [14C]hydrocortisone and [14C]testosterone. Systemic studies were also conducted to correct for incomplete urinary excretion. In addition, a single stratum corneum correction factor was developed from published data to enable the guinea pig ear skin to be directly compared with human forearm skin. A comparison of human percutaneous absorption with the corrected guinea pig ear absorption shows a high correlation for both hydrocortisone and testosterone. The effects of ambient changes in relative humidity are also discussed with respect to in vivo percutaneous absorption.
mesh_terms: D000287:Administration, Topical; D000818:Animals; D004431:Ear, External / Q000378:metabolism*; D006168:Guinea Pigs; D006813:Humidity; D006854:Hydrocortisone / Q000378:metabolism; D007274:Injections, Intraperitoneal; D008297:Male; D012869:Skin Absorption; D013997:Time Factors
chemical_list: D006854:Hydrocortisone