Farley J R, Puzas J E, Baylink D J
Miner Electrolyte Metab. 1982 Jun;7(6):316-23.
Chicken skeletal alkaline phosphatase is subject to competitive inhibitions by vanadate (Ki = 0.38 mM in carbonate, Ki = 0.08 mM in Tris, both at pH 7.4) and phenylphosphonate (Ki = 15 mM in carbonate, Ki = 1.3 mM in Tris, both at pH 7.4), and uncompetitive inhibition by levamisole (Ki = 0.08 mM in carbonate, Ki = 0.10 mM in Tris, both at pH 7.4). The competitive inhibitors were more effective in Tris buffer because nonreactive ternary complexes were formed between alkaline phosphatase, the inhibitor and Tris. The effects of vanadate, phenylphosphonate and levamisole on the proliferation of embryonic chick calvarial cells in vitro were biphasic. Low doses of each agent stimulated 3H-thymidine incorporation into TCA-insoluble material; higher doses were inhibitory. Neither effect could be attributed to inhibition of alkaline phosphatase activity (e.g. 20 microM vanadate should inhibit alkaline phosphatase by 3% but stimulated cell proliferation by 187%; 50 microM vanadate should inhibit alkaline phosphatase by 7% but inhibited 3H-thymidine incorporation by 90%). None of the alkaline phosphatase inhibitors tested affected the cellular concentration of the enzyme during the 24-hour incubation. These studies indicate that alkaline phosphatase inhibitors can have nonspecific effects on bone cells in culture, and that for cells in the osteoblast cell line, an inhibition of alkaline phosphatase activity is not consistently related to a decrease in cell proliferation.
鸡骨碱性磷酸酶受到钒酸盐（在pH 7.4的碳酸盐缓冲液中Ki = 0.38 mM，在Tris缓冲液中Ki = 0.08 mM）和苯膦酸盐（在pH 7.4的碳酸盐缓冲液中Ki = 15 mM，在Tris缓冲液中Ki = 1.3 mM）的竞争性抑制，以及左旋咪唑（在pH 7.4的碳酸盐缓冲液中Ki = 0.08 mM，在Tris缓冲液中Ki = 0.10 mM）的非竞争性抑制。竞争性抑制剂在Tris缓冲液中更有效，因为碱性磷酸酶、抑制剂和Tris之间形成了无反应性的三元复合物。钒酸盐、苯膦酸盐和左旋咪唑对体外培养的胚胎鸡颅骨细胞增殖的影响是双相的。每种试剂的低剂量刺激3H-胸腺嘧啶掺入三氯乙酸不溶性物质；高剂量则具有抑制作用。这两种作用都不能归因于碱性磷酸酶活性的抑制（例如，20 microM钒酸盐应抑制碱性磷酸酶3%，但刺激细胞增殖187%；50 microM钒酸盐应抑制碱性磷酸酶7%，但抑制3H-胸腺嘧啶掺入90%）。在24小时孵育期间，所测试的碱性磷酸酶抑制剂均未影响细胞内该酶的浓度。这些研究表明，碱性磷酸酶抑制剂可对培养的骨细胞产生非特异性影响，并且对于成骨细胞系中的细胞，碱性磷酸酶活性的抑制与细胞增殖的减少并不总是相关的。
