Renal excretion of phosphorus in nephropathy dogs under dopaminergic stimulation/Excrecao renal de fosforo em caes nefropatas sob estimulacao dopaminergica

The dopamine has a wide spectrum of action on the urinary system. Increases in glomerular filtration rate, renal blood flow, sodium and phosphate fractioned excretion are renal effects expected in healthy people. Thus, this study was conducted in order to test the hypothesis that the dopamine is efficient to increase the fractioned excretion of phosphorus in nephropathic dogs. Five healthy dogs and four dogs nephropathic, predominantly with tubule-interstitial illness were submitted to a solution control infusion (NaCl 0.9%) and to a dopamine solution in two different rates of infusion (1 [micro]g [kg.sup.-1] [min.sup.-1] and 3 g [kg.sup.-1] [min.sup.-1]) and were assessed before, during, and 30 minutes after the infusion. The healthy dogs presented a significant increase (P[less than or equal to]0.05) in the fractioned excretion and renal excretion of phosphate during the infusion of 3 [micro]g [kg.sup.-1] [min.sup.-1], however, the seric concentration remained without alterations during the treatment. The nephropathic dogs presented a significant increase (P