title: Kinetics of blood flow after topical application of benzyl nicotinate on different anatomic sites.
abstract: Cutaneous characteristics, e.g., thickness of the SC and density of follicles, affect the penetration of topically applied substances. In the present study, the penetration of benzyl nicotinate, causing a vasodilation, was studied on three anatomic sites (forearm, forehead and calf) differing in their skin characteristics. Therefore, the blood flow of the superficial dermal plexus and that of the larger capillaries in the deeper skin layers was simultaneously measured using a laser Doppler flowmeter. In addition, the cutaneous temperature and redness were determined as a function of time. These four biological reactions were measured in turn on a skin area treated with a gel containing benzyl nicotinate and on an untreated control area. The highest basal levels were observed on the forehead. Topical application of benzyl nicotinate resulted in an increase in each biological response. Compared to the other sites, the maximal values were reached earliest on the forehead, which also showed the fastest decrease. No significant differences were obtained comparing the kinetic data of the calf with that of the forearm. The results indicate an additional contribution by the numerous vellus hair follicles of the forehead to the penetration and exposure of the drug.
authors.affiliation: Center of Experimental and Applied Cutaneous Physiology, Department of Dermatology, Venerology and Allergology, Charité - Universitätsmedizin Berlin, 10098 Berlin, Germany.
authors.forename: Ute
authors.initials: U
authors.lastname: Jacobi
authors.forename: Marco
authors.initials: M
authors.lastname: Kaiser
authors.forename: Wolfram
authors.initials: W
authors.lastname: Sterry
authors.forename: Jürgen
authors.initials: J
authors.lastname: Lademann
mesh_terms: D000287:Administration, Topical; D000328:Adult; D005542:Forearm / Q000098:blood supply; D005546:Forehead / Q000098:blood supply; D006801:Humans; D007866:Leg / Q000098:blood supply; D008297:Male; D009539:Nicotinic Acids / Q000008:administration & dosage / Q000494:pharmacology*; D012039:Regional Blood Flow / Q000187:drug effects; D012867:Skin / Q000098:blood supply*; D012869:Skin Absorption; D014664:Vasodilation / Q000187:drug effects; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D009539:Nicotinic Acids; D014665:Vasodilator Agents; C025653:nicotinic acid benzyl ester