Suzuki K
Gan. 1978 Apr;69(2):229-35.
The distribution of 4-nitroquinoline 1-oxide (4-NQO) reductase, assumed to be closely related to the carcinogenesis of 4-NQO, was investigated in the mucosa of canine digestive tract, and its results indicated following points. 1) The activity of 4-NQO reductase was highest in the esophagus, next in the stomach, and remarkably low in the small and large intestines. 2) There is no significant difference in the 4-NQO reductase activity between the upper, middle, and lower portion of the esophagus, but its activity was higher in the female than in the male in its upper and middle portions. 3) Among the esophageal tissue, its activity was high only in the mucous epithelium and very low in all other layers. 4) Most of the enzymic activity in the esophageal mucosa existed in the cytosol fraction and activity of the microsome fraction was remarkably low. Even if NADPH or NADH was used as the hydrogen donor, its activity was not different in the cytosol fraction, but the former was a better hydrogen donor in the microsome fraction. 5) In the gastric mucosa, the enzymic activity was equally high in various portions of the corpus ventriculi; the greater and lesser curvatures, anterior and posterior parietes, and fundus. It was remarkably low only in the pyloric antrum.
对4-硝基喹啉1-氧化物（4-NQO）还原酶的分布进行了研究，该酶被认为与4-NQO的致癌作用密切相关，研究对象为犬消化道黏膜，结果表明以下几点。1）4-NQO还原酶的活性在食管中最高，其次是胃，在小肠和大肠中极低。2）食管上、中、下段的4-NQO还原酶活性无显著差异，但其活性在食管上段和中段女性高于男性。3）在食管组织中，其活性仅在黏液上皮中较高，在所有其他层中极低。4）食管黏膜中的大部分酶活性存在于胞质溶胶部分，微粒体部分的活性极低。即使使用NADPH或NADH作为氢供体，其在胞质溶胶部分的活性也没有差异，但在微粒体部分前者是更好的氢供体。5）在胃黏膜中，胃体各部位的酶活性同样较高；大弯和小弯、前壁和后壁以及胃底。仅在幽门窦中显著较低。
