Abstract
The dorsal skin topically treated wiht 0.5 and 30% solution of manganese ethylene bis (Maneb), a kind of dithiocarbamate fungicides, for 7 consecutive days was examined histopathologically in Wistar-derived inbred hypotrichotic WBN/ILA-Ht rats (HtRs). At day 1 after cessation of the treatment, except for slight inflammatory cell infiltration around hair follicles, no prominent histopathological changes were found. At 2 weeks after cessation of the treatment, prominent degeneration of epithelial cells characterized by pyknosis or karyorrhexis was found in the epithelial root sheath of hair follicles, and the nuclei of such epithelial cells were strongly stained by the TUNEL method. Thus, Maneb caused delayed-type lesions in the epithelial root sheath of hair follicles due to apoptosis.
