Gastric nitrate reduction and nitrosation of trimethylurea in swine treated with pentagastrin or cimetidine.
Gastric nitrate reduction and nitrosation of trimethylurea in swine treated with pentagastrin or cimetidine.
复制标题
用五肽胃泌素或西咪替丁治疗的猪体内胃硝酸盐还原和三甲基脲亚硝化。
DOI：
10.1093/carcin/12.1.141
复制
发表时间：
1991
期刊：
影响因子：
4.7
通讯作者：
Hotchkiss,JH
中科院分区：
文献类型：
--
作者：
Maragos,CM;Klausner,KA;Shapiro,KB;Hotchkiss,JH
用西咪替丁处理猪，以量化硝酸盐还原为亚硝酸盐和胃中形成的N-亚硝基三甲基脲（NTMU）在类似的条件下，在胃酸缺乏的人胃。胃造瘘猪滴注6.0 mmol硝酸盐在50 ml水中，之后监测胃硝酸盐，亚硝酸盐和pH值。在胃内亚硝酸盐浓度达到峰值后10分钟，通过瘘管滴入250 μmol溶于50 ml水中的三甲基脲。用五肽胃泌素刺激的动物进行类似的实验，以定量胃pH和微生物群落对硝酸盐、亚硝酸盐和NTMU形成的存在的影响。在西咪替丁处理猪（pH升高）的胃中，硝酸还原酶微生物定殖至104-107/ml胃液水平。在给予硝酸盐后60分钟，西咪替丁给药动物的胃内亚硝酸盐浓度达到最大值370-2085 μM。在西咪替丁或五肽胃泌素刺激的动物中，三甲基脲仅轻微亚硝化（<0.1 /μmol/1胃液）。在高pH值下，在大量亚硝酸盐存在下，NTMU的产率较低，表明猪胃中存在的硝酸盐还原菌在体内不催化三甲基脲亚硝化。
Swine were treated with cimetidine in order to quantify the reduction of nitrate to nitrite and the gastric formation ofN-nitrosotrimethylurea (NTMU) under conditions similar to those in the achlorhydric human stomach. Gastric-fistulated swine were instilled with 6.0 mmol of nitrate in 50 ml water, after which gastric nitrate, nitrite and pH were monitored. Trimethylurea, 250 μmol in 50 ml water, was instilled via the fistula 10 min following the peak gastric nitrite concentration. Similar experiments were conducted with pentagastrinstimulated animals, in order to quantitate the effect of gastric pH and microflora on the presence of nitrate, nitrite and NTMU formation. The stomachs of cimetidine-treated pigs (elevated pH) were colonized by nitrate reductase organisms to levels of 104–107/ml gastric fluid. Gastric nitrite concentration in cimetidine-treated animals reached a maximum of 370–2085 μM, 60 min following the nitrate dose. Trimethylurea was only marginally nitrosated (<0.1 /μmol/1 gastric fluid) in cimetidine- or pentagastrin-stimulated animals. The low yield of NTMU at elevated pH, in the presence of substantial nitrite, suggests that the nitrate-reducing bacteria present in the porcine stomach did not catalyze trimethylurea nitrosationin vivo.
登录
查看更多内容
注射干扰素敏感型和干扰素耐药型白血病细胞的小鼠体内干扰素的抗肿瘤作用。
影响因子：
6.4
作者：
F. Belardelli;I. Gresser;C. Maury;M. Maunoury
通讯作者：
M. Maunoury
重组小鼠干扰素-γ和胞壁酰二肽协同激活小鼠巨噬细胞的抗肿瘤特性。
影响因子：
4.4
作者：
I. Saiki;I. Fidler
通讯作者：
I. Fidler
T 细胞杂交瘤产生的巨噬细胞激活因子：理化和生物合成与γ-干扰素相似。
DOI：
--
发表时间：
1983
期刊：
Journal of immunology (Baltimore, Md. : 1950)
影响因子：
--
作者：
Schreiber,RD;Pace,JL;Russell,SW;Altman,A;Katz,DH
通讯作者：
Katz,DH
重组人干扰素-α B/D 杂交体对人肿瘤细胞系的直接抗增殖作用。
影响因子：
11.2
作者：
I. Fidler;R. Heicappell;I. Saiki;M. Grütter;M. Horisberger;J. Nuesch
通讯作者：
J. Nuesch
用干扰素或干扰素诱导剂聚肌苷-聚胞苷酸调节小鼠中 5-氟尿嘧啶诱导的毒性。
影响因子：
11.2
作者：
Stolfi,RL;Martin,DS;Sawyer,RC;Spiegelman,S
通讯作者：
Spiegelman,S