RESUMO
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.
Assuntos
Soluções Hipertônicas/farmacocinética , Absorção Intestinal/fisiologia , Distúrbios Nutricionais/fisiopatologia , Sódio/metabolismo , Animais , Modelos Animais de Doenças , Soluções Hipertônicas/administração & dosagem , Masculino , Manitol/administração & dosagem , Manitol/farmacocinética , Ratos , Ratos Wistar , Solução Salina Hipertônica/administração & dosagem , Solução Salina Hipertônica/farmacocinéticaRESUMO
Two groups of nine weanling male rats each were fed different diets for 60 days. Group A (control) was fed a full casein diet containing 17% protein. The group B received the same diet plus nitrite, fried bacon and proline. Diet B induced increased body weight gain and increased plasma l-lactic acid and cholesterol levels, as well as a decrease in plasma selenium. We suggest that the adverse effects of diet B are related to peroxidation, with an increased nutritional need for selenium.