MATERIALS AND METHODS

Approximately 300 biopsy specimens from the skin of the deltoid regions and the forearms of normal male volunteers, ranging in age from 19 to 34, were utilized for the study of the histology of normal skin. Informed consent was obtained from all volunteers. Biopsy specimens were procured with a Keyes 4-mm cutaneous punch, using field anesthesia with 1 or 2% lidocaine without epinephrine. The anesthetic was injected at 4 sites in the periphery of the area to be biopsied. Fixation was carried out for 5 hr at room temperature in a Karnovsky's fixative [4] composed of 2% paraformaldehyde, 2.5% glutaraldehyde, and 0.025% CaC12 in 0.1 M cacodylate buffer at pH 7.4 [2]. Postfixation in osmium tetroxide was followed by dehydration and embedding in Epon [1]. One-fLm-thick sections, approximately 5 to 8 mm on edge, were stained with Giemsa's reagent. At least two observers evaluated all sections at magnifications up to 1000x. One observer (MM) performed quantitative