ABSTRACT
This chapter aims to assess how and where prostaglandins (PGs) stimulate bone resorption. Comprehensive descriptions can be found in texts such as that by H. Rasmussen and P. Bordier, and reviews related to resorption in more specific pathologies are indicated. With the exception of some types of tumor cells which can invade and destroy bone, the osteoclast (OC) is undoubtedly the major bone-resorbing cell. Tissue culture experiments have also shown that stimulation of bone resorption by PGs is correlated with increased OC activity, in common with the bone-resorbing hormones parathormone and 1,25-dihydroxycholecalciferol. Addition of calcitonin to isolated OCs inhibits their movement and inhibits bone resorption in culture. Treating the net loss of bone as a disturbance of the resorption/formation equilibrium in favor of resorption, it is clear that PGs could cause this by altering either the amount of bone resorbed or the amount of bone formed.
