Fig. 3.

Apoptosis in velvet skin, perichondrium and mesenchyme. TUNEL staining, with methyl green counterstain. (A) Velvet skin; no apoptotic cells are detected in epidermis or dermis. (B) Higher power view to show apoptotic cells associated with hair follicles (arrows). (C) Perichondium/mesenchyme. There are large numbers of apoptotic cells in the perichondrium (fp) and subjacent outer (om) and inner (im) mesenchyme. (D) A significant proportion of chondroprogenitors are apoptotic. Bars: A, 200 µm; B, 32 µm; C, 100 µm; D, 50 µm.