RESUMEN
The effect of an 8 hour-period of water deprivation on fluid and electrolyte renal excretion was investigated in male Wistar rats infected with the strain Sao Felipe (12SF) of Trypanosoma cruzi, in comparison with age and sex matched non-infected controls. The median percent reductions in the urinary flow (-40 per cent v -63 per cent) and excretion of sodium (-57 per cent v - 79 per cent) were smaller in chagasic than in control rats, respectively. So, chagasic rats excereted more than controls. On the other hand, the median percent decrement in the clearance of creatinine was higher in chagasic (-51 per cent) than in controls (-39 per cent). Thus, chagasic rats showed some disturbed renal hydroelectrolytic responses to water deprivation, expressed by smaller conservation, or higher excretion of water and sodium in association with smallerglotmerular filtration rate. This fact denoted an elevation in the fractional excretion of sodium and water.