Inflammation experimentale et taux proteique alimentaire chez des rats intoxiques subchroniquement au nabame

Abstract

In research on new toxicity tests, attempts have been made to measure the response to an inflammatory type of attack. Groups of rats were fed diets containing various levels of protein (0, 3·5, 9, 26 and 81% casein) or a standard laboratory chow diet, and each group was further divided into subgroups given Nabam, disodium N,N'-ethylenebis(dithiocarbamate), at a dietary level of 0, 10, 50, 100, 500, 1000 or 2000 ppm. The inflammatory response was followed in these animals by determining the levels of total mucopolysaccharides, mucopolysaccharides containing hexuronic acid, mucopolysaccharides containing N-acetylneuraminic acid, total collagen and neutrosoluble, acid-soluble, labile (at 60°C) and insoluble collagen fractions in an experimental granuloma. In animals on a normal diet, Nabam administration reduced both the fresh weight of the granuloma and the levels of these different constituents, in a dose-related manner. When the protein level of the diet was reduced, the inflammatory reaction showed a corresponding decrease, an effect clearly accentuated by Nabam; the lower the protein level, the lower the effective dose of Nabam. Nabam affected mainly the fresh weight of the granuloma expressed in relation to body weight, the levels of mucopolysaccharides, particularly the soluble fractions, and the level and distribution of collagen. This test of experimental inflammation is a sensitive method for the early detection of a toxic effect and for relating an organism's defensive capacity to its nutritional state.