Enhancement of sodium intestinal secretion in relation to absorption in malnourished rats. Hyperosmolar challenge.

Two experimental models were tried in young malnourished rats in order to study effect of an hyperosmolar challenge in the small intestine on the bi-directional fluxes of sodium. Weanling rats were fed with energy restricted diets. In model I 1 mL of NaCl 900 mOsm/kg was introduced in the small intestine of the rats and left from 5 up to 70 min, in order to determine the moment of higher net Na+ secretion, which occurred at 10 min. In model II, the bi-directional fluxes of Na+ and Cl- were studied using NaCl or mannitol 900 mOsm/kg under the effect of mecholil, atropine or 2-4 dinitrophenol, for 10 min. Mecholil decreased the Na+ absorption enhancing the net secretion. Control rats were used as reference. In the restricted diets animals occurred an increase of the net secretion stimulated by NaCl 900 mOsm/kg, and this effect was enhanced by mecholil. It is suggested that in malnutrition there is an impairment in Na- intestinal absorption.

Rice and beans--effect of milk, mineral, and vitamin A, on weight gain, food intake, and body protein retention.

Weanling rats were fed on diets of rice/beans (RB) with or without mineral (M) supplement; vitamin A (A); M + A (MA); or milk (L), containing from 3 to 14% protein. As determined by various measures, the best results were observed in the group fed the RB diet, supplemented with L. This group was followed by those receiving the MA and M diets. Protein utilization in the RB diet, as well as minimum protein requirement for maintaining body weight, depend on the supplementary nutrients. The mechanism of this effect may be related to the appetite of the animals and to the voluntary intake, which is influenced and regulated by the diet composition.

Rice and beans: effect of milk, mineral, and vitamina A, on weight gain, food intake, and body protein retention

Ratas recién destetadas fueron alimentadas con dietas de: arroz/frijoles (RB) suplementadas o no con minerales (M); vitamina A (A); M + A (MA), o leche (L), que contenían de 3 a 14% de proteína. Según se determinó a través de diversas mediciones, los mejores reutlados se observaron en el grupo alimentado con la dieta RB suplementada con L, seguido por los grupos que recibieron las dietas MA y M. La utilización proteínica de la dieta de RB, así como el requerimiento mínimo de proteína para mantenimiento de peso corporal, depende de los nutrientes suploementarios. Puede que el mecanismo de este efecto esté relacionado con el apetito de los animales y con la ingesta energética voluntaria, la que es influencia y regulada por la composición d ela dieta

Lactose load diet effect in rats.

Weanling and young adult rats were fed diets containing lactose (L) up to 50 g per 100 g diet for 15 days. The growth rats variation (W), fecal pH, net protein ratio (NPR) and protein efficiency ratio (PER) were determined. In weanling as well as in young adult rats an impairment of L was only detected for higher levels (greater than 20%), and diarrhea occurred only at 50%. The NPR and PER were partially effected by L because of the stimulation of appetite between 1 and 5 g%. The results for 10 and 20 g% of L were not different from controls. It was concluded that rats are not intolerant to levels of L less than or equal to 20%. The evaluation of protein quality in presence of L must be conducted with adapted methodology.

Lactose load diet effect in rats.

Ratos recem desmamados ou jovens adultos foram alimentados por 15 dias com dietas contendo lactose (L) ate niveis de 50%g.Determinou-se a velocidade de crescimento, pH fecal, indice liquido da eficiencia proteica (PER). Em todos os animais foi observado efeito de L da dieta apenas para teores de L > 20g%, com aparecimento de diarreia apenas em 50g%. Quanto as determinacoes de NPR e de PER houve influencia do incremento do apetite influenciado por teores de L entre 1 e 5g%, entretanto, para L, 10 ou 20g%, os valores foram semelhantes aos dos controles. Conclui-se que os ratos nao sao intolerantes a lactose ate valores de 20%, mas os metodos de avaliacao da qualidade proteica devem ser adaptados