Mizuno K, Gotoh M, Hashimoto S, Ojima M, Fukuchi S
Nihon Naibunpi Gakkai Zasshi. 1985 May 20;61(5):571-80. doi: 10.1507/endocrine1927.61.5_571.
The biochemical properties of renin, extracted from human pituitary specimens obtained at autopsy, were studied using a specific antirenin antibody raised against human kidney renin. The following results were obtained. The molecular weight of pituitary renin was estimated to be about 37,000 daltons by gel filtration through Sephadex G-100. The optimum pH of pituitary renin was between 6.0 approximately 7.0, while that of a renin-like substance which did not react with the antirenin antibody had an acidic pH of 4.0, with a pH comparable to that of the cathepsin D-like enzyme in the pituitary tissue. The presence of two different isoelectric-point species of pituitary renin was revealed by isoelectric focusing, one with a point of pH 4.47 and the other with that of pH 5.77. The Km value of pituitary renin was 37.9 microM for synthetic human renin substrate. Affinity chromatography of the pituitary renin on a Concanavalin-Sepharose column showed that most (87.4%) of the pituitary renin did not contain glycoprotein residues. Treatment with either trypsin or glandular kallikrein increased the renin activity, indicating the presence of an inactive form of renin in the pituitary tissue. From these findings, it is concluded that specific renin exists in human pituitary tissue. It seems likely that the pituitary renin is of local origin rather than contamination of the circulating enzyme.
利用针对人肾素产生的特异性抗肾素抗体，对从尸检获得的人垂体标本中提取的肾素的生化特性进行了研究。得到了以下结果。通过Sephadex G - 100凝胶过滤法估计垂体肾素的分子量约为37,000道尔顿。垂体肾素的最适pH值在6.0至7.0之间，而一种不与抗肾素抗体反应的肾素样物质的最适pH值呈酸性，为4.0，与垂体组织中组织蛋白酶D样酶的pH值相当。等电聚焦显示垂体肾素存在两种不同等电点的类型，一种等电点为pH 4.47，另一种为pH 5.77。垂体肾素对合成人肾素底物的Km值为37.9 microM。垂体肾素在伴刀豆球蛋白 - 琼脂糖柱上进行亲和层析显示，大部分（87.4%）垂体肾素不含有糖蛋白残基。用胰蛋白酶或腺体激肽释放酶处理可增加肾素活性，表明垂体组织中存在无活性形式的肾素。从这些发现可以得出结论，人垂体组织中存在特异性肾素。垂体肾素似乎很可能是局部来源，而非循环酶的污染。
