Effectiveness of phosphocitrate and N-sulpho-2-amino tricarballylate, a new analogue of phosphocitrate, in blocking hydroxyapatite induced crystal growth and calcium accumulation by matrix vesicles.

Phosphocitrate and its analogue N-sulpho-2-amino tricarballylate were compared with ethane-1-hydroxy-1,1-diphosphonate for inhibition of calcium phosphate crystallization in hydroxyapatite induced crystal growth and 45Ca uptake by matrix vesicles. Phosphocitrate (1 microM) was the most potent inhibitor followed by ethane-1-hydroxy-1,1-diphosphonate and N-sulpho-2-amino tricarballylate, the latter requiring a high concentration (100 microM) to be equally effective as an inhibitor.