Insulin-like growth factor 1 (IGF-1) antler-stimulating hormone?

We have investigated the possibility that IGF-1 may play a role in the regulation of antler development. Plasma IGF-1 concentrations were measured throughout the first period of development of the pedicle and first antler of red deer (Cervus elaphus) to determine whether a relationship existed between growth of antler cartilage (velvet antler) and IGF-1. We report that plasma levels of IGF-1 are significantly elevated during the velvet antler growing phase relative to the other phases of pedicle and first antler development and a strong positive correlation exists between antler growth rate and circulating concentrations of IGF-1. As IGF-1 has been demonstrated to influence cartilage growth, we suggest that IGF-1 is a candidate as an antler stimulating hormone.