Concentrations of adrenocorticotropic hormone too low to effect cortisol enhance osteogenesis in vitro and in vivo

After finding that minimal amounts of adrenocorticotropic hormone (ACTH(1-24)) prevented osteonecrosis in rabbits, we studied bone formation at nanomolar ACTH(1-24), in vivo in rabbits and in vitro in human osteoblasts. ACTH(1-24) in rabbits at 0.6 μg/kg/day had no measurable effect on cortisol. Groups of five rabbits given 0.6 μg/kg/day of ACTH(1-24) enhanced trabecular bone in the rabbit femoral head relative to saline-treated controls (controls), increased bone volume/total volume (BV/TV) by...