Peake M J, Pejakovic M, White G H
Department of Biochemistry and Chemical Pathology, Flinders Medical Centre, Bedford Park, South Australia.
J Clin Pathol. 1988 Feb;41(2):202-6. doi: 10.1136/jcp.41.2.202.
Intestinal alkaline phosphatase activity was measured using levamisole inhibition, and results were compared with a previously reported method using L-phenylalanine. Sixty two per cent intestinal, 39% placental, and 1.3% of either bone or liver alkaline phosphatase activity remained when alkaline phosphatase activity was inhibited in a 2-amino-2-methyl-1-propanol (AMP) buffer reagent system with 10 mmol/l levamisole (final assay concentration 8.1 mmol/l). The assay imprecision (SD) was 0.6 U/l compared with 3.9 U/l using L-phenylalanine for specimens with total alkaline phosphatase activity less than 250 U/l (reference range 30-120 U/l). In serum pools with raised total alkaline phosphatase activity errors in recovered intestinal activity were small (usually less than 3 U/l) when intestinal alkaline phosphatase was added. Much larger errors and many underestimated results were found using L-phenylalanine. For non-haemolysed specimens it is concluded that an assay based on levamisole inhibition provides a better measure of intestinal alkaline phosphatase activity than L-phenylalanine.
采用左旋咪唑抑制法测定肠道碱性磷酸酶活性，并将结果与先前报道的使用L-苯丙氨酸的方法进行比较。在含有10 mmol/l左旋咪唑（最终测定浓度8.1 mmol/l）的2-氨基-2-甲基-1-丙醇（AMP）缓冲试剂系统中抑制碱性磷酸酶活性时，分别有62%的肠道、39%的胎盘以及1.3%的骨或肝脏碱性磷酸酶活性保留下来。对于总碱性磷酸酶活性低于250 U/l（参考范围30 - 120 U/l）的标本，该测定方法的不精密度（标准差）为0.6 U/l，而使用L-苯丙氨酸时为3.9 U/l。在总碱性磷酸酶活性升高的血清混合液中，添加肠道碱性磷酸酶时，回收的肠道活性误差较小（通常小于3 U/l）。使用L-苯丙氨酸时发现误差大得多且许多结果被低估。对于非溶血标本，得出的结论是基于左旋咪唑抑制的测定方法比L-苯丙氨酸能更好地测定肠道碱性磷酸酶活性。
