The intragastric host-mediated assay (h.m.a.) was devised and carried out with a view to assessing the formation of direct mutagens in the gastrointestinal tract of mammals. The h.m.a. consists in the injection of nitrosable compounds. NaNO 2 and cells of the yeast S. pombe, by gavage into the animals' stomachs and in the recovery of the target cells from the faeces for mutation-induction analysis. Methylurea was chosen as a model nitrosable compound, and the effects of nitrosation modulators such as ascorbic acid and thiocyanate were studied. Cimetidine, a drug nitrosable in vitro, was tested with the system. Positive results were obtained only at very large doses and in artificially produced low pH. The new host-mediated assay seems to be efficient in revealing the formation, in vivo, of direct, short-living mutagens.
|Autori:||Barale R; Zucconi D; Romano M; Loprieno N|
|Titolo:||The intragastric host-mediated assay for the assessment of the formation of direct mutagens in vivo.|
|Anno del prodotto:||1983|
|Appare nelle tipologie:||1.1 Articolo in rivista|