Nishihara Y, Hayashi Y, Fujii T, Adachi T, Stigbrand T, Hirano K
Department of Pharmaceutics, Gifu Pharmaceutical University, Japan.
Biochim Biophys Acta. 1994 Dec 14;1209(2):274-8. doi: 10.1016/0167-4838(94)90196-1.
The content of alkaline phosphatase isozymes in various brain regions was determined by monoclonal immunocatalytic assays. The levels of the isozymes in human brain tissues were low compared with those in other human tissues, liver, kidney, bone, intestine and placenta. Plexus chorioideus in the brain, however, was found to express significant amounts of alkaline phosphatase activity. The purified isozyme from human plexus chorioideus demonstrated a single 70 kDa protein band on SDS-polyacrylamide gel which coincides with that of tissue-unspecific alkaline phosphatase from human liver. The isozyme expressed in the plexus was confirmed to be the tissue-unspecific alkaline phosphatase isozyme with regard to its reactivity with monoclonal antibodies specific for liver alkaline phosphatase, heat stability, and the inhibition by amino acids. This finding adds new dimensions to the functional role this isozyme may play.
采用单克隆免疫催化分析法测定了不同脑区碱性磷酸酶同工酶的含量。与人体其他组织（肝脏、肾脏、骨骼、肠道和胎盘）相比，人脑组织中该同工酶的水平较低。然而，发现脑内脉络丛表达大量碱性磷酸酶活性。从人脉络丛中纯化得到的同工酶在SDS聚丙烯酰胺凝胶上显示出一条单一的70 kDa蛋白带，这与来自人肝脏的组织非特异性碱性磷酸酶的蛋白带一致。就其与肝脏碱性磷酸酶特异性单克隆抗体的反应性、热稳定性以及氨基酸抑制作用而言，脉络丛中表达的同工酶被确认为组织非特异性碱性磷酸酶同工酶。这一发现为该同工酶可能发挥的功能作用增添了新的维度。
