Krizbai I, Joó F, Pestean A, Preil J, Bötcher H, Wolff J R
Laboratory of Molecular Neurobiology, Institute of Biophysics, Biological Research Center, Szeged, Hungary.
Neuroscience. 1997 Feb;76(3):799-807. doi: 10.1016/s0306-4522(96)00397-1.
Localization of acid phosphatases was studied with the use of beta-glycerophosphate and p-nitrophenyl phosphate as substrates in the brain with special emphasis on the olfactory system of adult rat at light and electron microscopic level. With the use of beta-glycerophosphate, a selective substrate for the lysosomal acid phosphatase, lead-containing reaction product was found in primary and secondary lysosomes of neurons, glial cells and perivascular macrophages as well as in the cytoplasm of olfactory sensory axons. Incubation with p-nitrophenyl phosphate as substrate additionally revealed a cytoplasmic isoform of acid phosphatase, which could not be inhibited by tartrate or fluoride and was predominantly located in dendrites. Acid phosphatase isoforms were biochemically characterized in samples prepared separately from the olfactory mucosa, olfactory nerve layer, olfactory bulb and its dendrodendritic synaptosomes isolated by subcellular fractionation. In the olfactory mucosa and olfactory nerve layer the lysosomal type (high molecular weight form) was the most prominent acid phosphatase form, whereas the isoform located in dendrites corresponded to the tartrate-resistant extralysosomal, cytosolic type (low molecular weight form). The functional significance of different isoforms of acid phosphatase in the olfactory sensory axons and dendritic elements is discussed.
以β-甘油磷酸酯和对硝基苯磷酸酯为底物，在光镜和电镜水平上研究了成年大鼠脑内酸性磷酸酶的定位，特别着重于嗅觉系统。使用溶酶体酸性磷酸酶的选择性底物β-甘油磷酸酯时，在神经元、神经胶质细胞和血管周围巨噬细胞的初级和次级溶酶体以及嗅觉感觉轴突的细胞质中发现了含铅反应产物。以对硝基苯磷酸酯为底物进行孵育时，还发现了一种酸性磷酸酶的细胞质同工型，它不受酒石酸盐或氟化物抑制，主要位于树突中。通过亚细胞分级分离从嗅觉黏膜、嗅神经层、嗅球及其树突-树突突触体中分别制备样本，对酸性磷酸酶同工型进行了生化特性分析。在嗅觉黏膜和嗅神经层中，溶酶体类型（高分子量形式）是最主要的酸性磷酸酶形式，而位于树突中的同工型则对应于抗酒石酸的溶酶体外、胞质类型（低分子量形式）。文中讨论了酸性磷酸酶不同同工型在嗅觉感觉轴突和树突成分中的功能意义。
