Characterization of the prostaglandin receptors in human osteoblasts in culture

Department of Medicine, Faculty of Medicine, Université de Sherbrooke, Sherbrooke, Canada.
Prostaglandins Leukotrienes and Essential Fatty Acids (Impact Factor: 2.35). 04/2001; 64(3):203-10. DOI: 10.1054/plef.1999.0127
Source: PubMed


Prostaglandins have complex actions on bone metabolism that depend on interactions with different types and subtypes of receptors. Our objective was to characterize the prostaglandins receptors present in primary cultures of human osteoblasts. RT-PCR analysis revealed the presence of DP, EP(4), IP, FP and TP receptor mRNA in primary cultures of human osteoblasts. FP receptor mRNA was detected only after 3 weeks of confluency, all the others were detected at every culture time tested. To verify the functionality of these receptors we challenged the cells with the prostanoids and synthetic analogues and determined the intracellular levels of cAMP. All receptors found by RT-PCR were coupled to second messengers except for the DP subtype. These results clearly show the presence of functional EP(4), IP, FP and TP receptors in human osteoblasts in culture.

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    • "PGE 2 has been demonstrated to exert both anabolic and catabolic effects depending on the activation of its specific receptor subtypes. In osteoblasts, three such receptors, EP1, EP2 and EP4, are present [33] [34]. PGE 2 signalling through the EP1 receptor enhances pro-anabolic effects such as bone formation, whereas signalling through the EP2 and EP4 receptors induces catabolic effects on bone [35] [36] [37]. "
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