Larsson A
Scand J Dent Res. 1976 Mar;84(2):63-75. doi: 10.1111/j.1600-0722.1976.tb00463.x.
The activity of a pyrophosphate-splitting tissue factor in jaws, teeth and intestinal mucosa has been studied by means of histochemistry. Freeze-cut, unfixed sections of whole animals were incubated in a buffered medium (pH 8.6) containing inorganic pyrophosphate (PP) Pb2+, Mg2+, and Zn2+ at various concentrations. The effects of compound R 8231, heat, aldehyde fixation, and demineralization with EDTA were also investigated. In sections showing optimal staining, deposition of incubation products was found in the stratum intermedium and the subodontoblastic cells of the developing tooth, in the osteoblastic layers, and at the surface of the intestinal mucosa. The hard tissues were also stained except in the demineralized sections. Treatment with heat or compound R 8231 resulted in loss of originally observed soft tissue staining while short-time demineralization with EDTA enhanced the staining reaction. It is argued that a nonspecific deposition of the capturing ion, Pb2+, can hardly explain the observed soft tissue staining. The results point to the presence of a PP-splitting enzyme, and it is suggested that the enzyme exhibits features of an alkaline phosphatase with PP-phospholhydrolytic properties rather than of an inorganic pyrophosphatase.
已通过组织化学方法研究了颌骨、牙齿和肠黏膜中焦磷酸分解组织因子的活性。将全动物的冷冻切片、未固定切片在含有不同浓度无机焦磷酸（PP）、Pb2+、Mg2+和Zn2+的缓冲介质（pH 8.6）中孵育。还研究了化合物R 8231、加热、醛固定以及用乙二胺四乙酸（EDTA）脱矿质的影响。在显示最佳染色的切片中，在发育中牙齿的中间层和成牙本质细胞下层、成骨细胞层以及肠黏膜表面发现了孵育产物的沉积。除脱矿质切片外，硬组织也被染色。加热或用化合物R 8231处理导致原本观察到的软组织染色消失，而用EDTA进行短时间脱矿质则增强了染色反应。有人认为，捕获离子Pb2+的非特异性沉积很难解释观察到的软组织染色现象。结果表明存在一种焦磷酸分解酶，并且有人提出该酶表现出具有焦磷酸磷水解特性的碱性磷酸酶的特征，而不是无机焦磷酸酶的特征。
