Fig. 2.

Innervation of epidermis and hair follicles in developing skin. (A-J) Histological sections of E12.0 (A), E13.5 (B), E16.5 (C), P0 (D-G) and P7.5 (H-J) mouse skin were co-labeled with antibodies against Nefh and VGLUT2 (A-D), Nestin and Krt14 (E,F), nestin and NMDAR (G,I,J) or Nefh and Krt14 (H). Single color panels are shown for nestin (I) and NMDAR (J) co-labeled P7 hair follicles. Arrows indicate innervation sites in the epidermis and follicles (A-C,E). Bracket delineates the triangular organization of Nestin⁺ hair follicle cells (E). Asterisks indicate outer track nestin⁺NMDAR⁺ cells (^**) or inner track nestin⁺NMDAR^– cells (^*). Dashed line demarcates the epidermal-dermal border (A-D) and hair follicle ORS cells (C,D,I,J). 2° hf, secondary hair follicle; 3° hf, tertiary hair follicle; CF, circumferential fiber; Derm, dermis; Epid, epidermis; LF, longitudinal fiber; Hb, hair bud; Hf, hair follicle; tSC, putative terminal Schwann cells.