Expression of PTHrP and the PTH/PTHrP receptor in growing red deer antler.

Antler growth is highly co-ordinated, so that trabecular bone and antler skin (velvet) develop together, at a rapid rate and in a manner reminiscent of their development in the fetus. Parathyroid hormone-related peptide (PTHrP) is expressed in both bone and skin, and is therefore a candidate to effect co-ordination between these tissues. The aim of this study was to localize the expression of PTHrP and its principal receptor, the parathyroid hormone/parathyroid hormone-related peptide receptor (PTH/PTHrPR), in antler ("spiker") of one-year-old red deer.

Mitotic activity in the growing red deer antler.

Antlers grow rapidly through the coordinated development of both osseocartilage and skin (velvet). The regional patterns of cell division in these two compartments were assessed by immunochemical detection of proliferating cell nuclear antigen (PCNA) in antlers from one-year-old red deer. The whole antler integument was in a state of growth and/or renewal, particularly the keratinocytes of the basal cell layer of the epidermis near the tip, and hair bulbs and sebaceous glands.