PTHrP(1-36) as a skeletal anabolic agent for the treatment of osteoporosis.

Abstract

Parathyroid hormone-related protein (1-36) [(PTHrP(1-36)] has been shown to be one of the authentic secretory forms of PTHrP. Human studies employing this peptide have demonstrated that it is equipotent to parathyroid hormone (1-34). This observation, together with the observations that: (1) both peptides employ the same receptors; (2) both bind to this PTH/PTHrP receptor with equal affinity and activate the PTH/PTHrP receptor intracellular signaling pathways with the same efficacy; (3) both peptides are effective anabolic skeletal agents in laboratory animals; and (4) PTHrP is likely to be the endogenous skeletal ligand for the PTH/PTHrP receptor, collectively suggest that PTHrP (1-36) should be as equally effective as PTH(1-34) as an anabolic skeletal agent. In this mini-review, the theoretical basis for the exploration and development of PTHrP(1-36) as a potential therapeutic agent for osteoporosis is considered.