title: Further studies on n-nitrosopyrrolidine and its precursors: Effects of ascorbic acid and vitamin E on tumor development in mice as related to consumption of cured meat.
abstract: Two experiments were carried out to ascertain if supplementation of a semipurified diet to Swiss-ICR mice with either ascorbic acid (AA), vitamin E (Vit E) or a combination of the two would modulate the carcinogenic effects of N-nitrosopyrrolidine (NPyr) and of its probable precursors (nitrite-N0(2) and pyrrolidine-Pyr) in Experiment I or of NPyr in Experiment II. Results indicated that neither AA nor Vit E modulated the carcinogenic effects of NPyr or of its probable precursors (NO(2) and Pyr). Results verified a previous report from our laboratory showing that NPyr increased the number of malignant tumors by some 5-8 fold over controls. There was a lower incidence of tumors in the control group on the semi-purfied diet than in the groups given NO(2) and Pyr, although both treatments had a low frequency of malignant tumors (1 63  versus 5 72  survivors). Results support our earlier study suggesting that neither NO(2) nor Pyr alone or in combination together contribute to cancer-at least in the laboratory mouse.
authors: Department of Food Science and Human Nutrition, Michigan State University, East Lansing, Michigan 48824, USA.
authors: A M
authors: AM
authors: Pearson
authors: S D
authors: SD
authors: Sleight
authors: R I
authors: RI
authors: Brooks
authors: J I
authors: JI
authors: Gray