Elder J B, Burdett K, Smith P L, Walters C L, Reed P I
IARC Sci Publ. 1984(57):969-74.
Intragastric nitrosation of proline (500 mg daily) was studied in eight volunteers and three duodenal ulcer patients. Daily urine outputs of N-nitrosoproline (NPRO) and N-nitrosothiazolidine-4-carboxylic acid (NTCA) were measured for two days before, two days during and two days after ingestion of H2 blocker (ranitidine). No increase in NPRO output was found with ranitidine, the trend being clearly towards decreased intragastric nitrosation of this amine. A significant (p less than 0.05) increase in NTCA occurred during H2 blockade, due to increased concentration of NTCA in urine. The biological significance of the presence of NTCA in urine is uncertain.
在8名志愿者和3名十二指肠溃疡患者中研究了脯氨酸(每日500毫克)的胃内亚硝化作用。在摄入H2阻滞剂(雷尼替丁)之前两天、期间两天和之后两天,测量了N-亚硝基脯氨酸(NPRO)和N-亚硝基噻唑烷-4-羧酸(NTCA)的每日尿量。雷尼替丁未使NPRO产量增加,趋势明显是该胺的胃内亚硝化作用降低。在H2阻滞剂作用期间,NTCA显著增加(p<0.05),这是由于尿液中NTCA浓度增加所致。尿液中存在NTCA的生物学意义尚不确定。