Effects of several detergents and dietary fiber added to a diet on intestinal sucrase activity in rats.

The role of dietary fiber in counteracting the toxic effect, and significant growth retardation, of some non-ionic detergents added to the diet has been observed by Ershoff et al. (1, 2), but the mechanism by which these chemicals and dietary fiber exert their effects on the physiological functions has remained unclear. We recently supposed that the primary toxic effect of these chemicals was the exfoliating or releasing effect on the brush border membrane in the small intestine, and that dietary fiber prevented this adverse effect of these chemicals. In the previous studies (3, 4) the segmental sucrase activity, sucrase activity per unit length of the small intestine, in rats fed on a diet consisting of the same composition remained at a constant level regardless of food consumed, and was adopted as a criterion of the representative integrity and function of the brush border membrane. And the relationships among changes in body weight, food consumption, fecal consistency and the segmental sucrase activity in rats fed on diets containing polyoxyethylene sorbitan monolaurate (Tween 20), trisodium salt of 1-(4-sulfo-1-naphthylazo)-2 naphthol-3, 6-disulfonic acid (amaranth), sodium laurylbenzene sulfonate, sodium oleate or magnesium sulfate and dietary fiber was investigated. Experimental results demonstrated evidence lending support to this hypothesis. The present study was undertaken to investigate changes in body weight, food consumption, fecal consistency and the segmental sucrase activity in rats fed on diets containing polyoxyethylene sorbitan monostearate (Tween 60), sodium tau rocholate (NaTC), sodium deoxycholate (DOC) or sorbitan monolaurate (Span 20) and the Gobo dietary fiber (GDF), which was used in the previous studies (3, 4), and to obtain additional evidence in support of the hypothesis. Male rats of the Wistar strain were used, the basal diet used being a 20% casein high-sucrose diet (3). Rats were fasted for 2 days, being refed on the experimental diets, which consisted of Tween 60, NaTC, DOC or Span 20 and GDF added to the