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Extracellular ATP acting through purinoceptors may be an important factor in the modulation of bone turnover. In this study we cloned and sequenced the P2Upurinoceptor from osteoclastoma, confirming the recently published human sequence. Furthermore, by the reverse transcriptase‐linked polymerase chain reaction (RT‐PCR) and Southern blotting we demonstrated expression of P2Ureceptor mRNA in bone, primary cultures of human bone‐derived cells, and two osteosarcoma cell lines, Saos2 and Te85. P2Ureceptor transcripts were identified in alkaline phosphatase‐positive human bone‐derived cells isolated by flow cytometry providing strong evidence for the expression of the P2Upurinoceptor in mature osteoblasts. P2Ureceptor transcripts were also detected in a purified giant cell population isolated from osteoclastoma, indicating that this receptor is also expressed by osteoclasts. These data suggest that purinergic agonists may play a role in the regulation of bone metabolism.

It has been proposed that Paget's disease of bone is caused by the infection of bone cells with one or several paramyxoviruses. In this study we used the polymerase chain reaction (PCR), which allows the detection of very low levels of a target nucleic acid sequence, to study cultures of pagetic bone cells and samples of pagetic bone. Oligonucleotide primers were designed to flank a sequence of the nucleocapsid genome of measles virus and canine distemper virus (CDV). Within this fragment there were contrasting restriction endonuclease sites specific to measles or CDV that allowed identification of the original template. We were unable to detect paramyxovirus RNA in four strains of human bone cells outgrown from pagetic bone and one strain derived from an uninvolved site of a patient with Paget's disease. Furthermore, paramyxovirus sequences were not detected in cDNA prepared from six samples of pagetic bone biopsies. The work presented here further questions the role of measles and CDV in the abnormal remodeling observed in Paget's disease.