HISTOLOGY AND CYTOCHEMISTRY OF HUMAN SKIN .6. THE DISTRIBUTION OF SULFHYDRYL AND DISULFIDE GROUPS

[摘要] In the epidermis, sulf hydryl and disulfide groups are distributed homogeneously from the basal layer to the stratum granulosum. The stratum corneum, which is slightly reactive in the sulfhydryl prepn. is strongly reactive in disulfide prepns. A narrow, parakeratotic layer of cells interposed between the stratum granulosum and stratum corneum contains a concn. of sulfhydryl and disulfide groups. This layer is comparable to the so-called keratogenous zone** in hard keratinization. In the epidermis of the palm and sole, the accumulation of sulfhydryl and disulfide groups is more intense than that in the skin elsewhere in the body. The basal cytoplasmic processes which extend from the lower side of the cells in the stratum basale, the intercellular bridges, the nodes of Bizzozero, and the tonofibrils are all reactive for sulfhydryl and disulfide groups. Sulfhydryl and disulfide groups were demonstrated neither in the keratohyalin nor in the trichohyalin granules of hair follicles. In active hair follicles, the external sheath is strongly and uniformly reactive to the sulfhydryl reagent. In the internal sheath, Henle''s layer is more strongly reactive than Huxley''s layer. The parakeratotic or keratogenous region of the hair root is intensely reactive for sulfhydryl groups. The distribution of disulfide groups in the external and internal sheath of the hair follicle is similar to that of the sulfhydryl groups. The keratinized hair shaft is reactive for disulfide groups. In resting hair follicles the epithelial sac, which contains the hair club, is moderately reactive for sulfhydryl groups but the club is almost unreactive. The keratinized rootlets of the club and the epidermal cells which anchor the club form a strongly reactive band around it. In disulfide prepns., the hair club and shaft are strongly reactive. Both the secretory and ductal portions of the apocrine and eccrine sweat glands are reactive to the sulfhydryl and disulfide reagents, the reaction being particularly conspicuous in the myoepithelial cells.