HISTOCHEMISTRY OF PLANTAR HYPERKERATOSES - A CONTRIBUTION TO THE PHYSIOLOGY OF THE SKIN SURFACE

[摘要] Esterases are demonstrable histochemically on the skin surface by means of tissue sections and of paper wipings from the surface. Sebum and sweat are the chief carriers of these esterases. Furthermore, esterases are carried in cornified cells to the surface of hyperkeratotic and parakeratotic areas. In hyperkeratotic sites, these esterases do not behave differently from those in the underlying epidermis in the presence of esterase inhibitors and activators (quinine hydrochloride, caffeine, eserine, glycerine, sodium taurocholate, NaF). In the normal plantar horny layer, the wave-crests (Unna) differ histochemically from the wave-troughs. The sweat ducts contain a PAS-ppsitive, Ninhydrin-Schiff-positive, and esterase-positive material which also stains for lipid. In clavi some of the sweat ducts are obstructed by parakeratotic material[long dash]and the ducts are less numerous and less evenly distributed than ordinarly. Different methods for demonstrating sulfhydryl groups are distinctly positive in parakeratotic and hyper-keratototic areas, except when using the technique of Bennett, which effects only a weak staining. Fungal mycelia present in the horny layers produced a positive esterase reaction. As a biochemical implication of our histochemical findings, it appears warranted to assume that an esterase mantle covers the skin surface.