Inorganic Phosphate, Pyrophosphate and the Diphosphonates Activate Bone (Calvaria) Glutaminase
Inorganic phosphate (Pi), pyrophosphate (PPi) and its synthetic analogues, dichloromethanediphosphonate (Cl2MDP) and 1-hydroxyethane-1, 1-diphosphonate (EHDP) compete for sites in bone mineral affecting the formation and dissolution of apatite.1 The diphosphonates may also affect the metabolism of bone and cartilage cells and possibly other tissues by interacting with enzymes or proteins which bind phosphate or phosphorylated intermediates. Available data indicate that Cl2MDP increases the production of CO2 from acetate, leucine, citrate and palmitate; stimulates the synthesis of collagen, proteoglycans and glycogen; increases alkaline phosphatase activity and inhibits lactate formation in cultured calvaria cells.2,3
KeywordsGlutamate Dehydrogenase Cartilage Cell Glutamine Metabolism Basal Salt Solution Krebs Cycle Intermediate
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