Figure 4. NSDHL expression in developing dorsal skin and hair follicles.

A. NSDHL staining in dorsal skin of a P2 WT pup shows strong signal in the sebaceous glands, and expression in the inner root sheath of the developing hair follicle, as well as the epidermis. B. In dorsal skin of a Bpa^1H P2 pup, regions lacking detectable NSDHL in the epidermis and developing hair follicles (left of arrowhead) appeared similar histologically to regions that stained positively for NSDHL (right of arrowhead). C. WT skin from P6 displayed strong NSDHL staining in the outer root sheath and moderate staining in the inner root sheath of the maturing hair follicle. D. In Bpa^1H skin at P6, NSDHL negative regions showed a thickening of the epidermis and dermis with developmentally delayed hair follicles. E. Higher magnification view of the sample shown in panel C. F. Higher magnification of the sample shown in panel D. G. NSDHL staining in dorsal skin of a Bpa^1H female at 8 weeks of age. Strong staining in sebaceous glands and the inner root sheath of anagen stage hair follicles is visible in the region to the right of the arrowhead. The area on the left shows virtually no staining in the enlarged sebaceous glands and mainly telogen stage hair follicles. No hair shafts are present within the hair follicles in this region. Abbreviations: De, dermis; Ep, epidermis; HF, hair follicle; HFB, hair follicle bulb; HS, hair shaft; IRS, inner root sheath; ORS, outer root sheath; SG, sebaceous gland. Size bars represent 100 µm.