PTGS2 and osteoporosis: Recombinant human PTH(1-34) is the only anabolic therapy currently approved in the United States for treatment of osteoporosis.(4–6) PTH is a potent inducer of COX-2 in osteoblasts via the cyclic adenosine monophosphate (cAMP) protein kinase A (PKA) pathway.(7–9) Because PTH and PGE2 can have similar effects on bone remodeling, it is possible that some of the local effects of PTH may be mediated via the induction of COX-2 expression and PGE2 production.