Intact kidney function during contralateral renal artery clamping in dogs

Experiments were carried out on 32 Nembutal anaesthetized mongrel dogs from both sexes. After 45 min control period unilateral renal ischemia was achieved by clamping the left renal artery for 90 min. In part of the experiments (n = 8) after clamp removal 3 consecutive 45 min periods were performed. The function of the intact right kidney was investigated. Mean arterial pressure (MAP), heart rate (HR), glomerular filtration rate (GFR), urine flow rate (V), fractional excretions of sodium (FENa), potassium (FEK) and chloride (FECl) and plasma levels of atrial natriuretic peptide, dopamine and antidiuretic hormone were evaluated. During ischemia MAP was elevated from 122.5 +/- 3.1 to 140.2 +/- 2.7 mmHg (p < 0.001), HR decreased from 119 +/- 4 to 102.5 +/- 3.9 beats/min (p < 0.01) as compared to the control period. GFR did not change significantly, while all excretory parameters increased: V from 8.7 +/- 1.2 to 14.5 +/- 1.7 microliters/min/gr kidney tissue (p < 0.05); FENa from 2.3 +/- 0.2 to 3.6 +/- 0.3% (p < 0.01); FEK from 40.0 < 3.5 to 51.2 < 2.8% (p < 0.05); FECl from 1.8 < 0.3 to 2.6 < 0.3% (p < 0.05). MAP remained elevated in the first and the second postischemic periods and was paralleled by the sustained increase in FENa and FECl, while FEK remained higher to the end of the experiment. ANP was significantly elevated during ischemia: on 75 min--p < 0.01 and on 105 min.--p < 0.05. AVP and dopamine showed no statistically significant changes during the investigated periods.(ABSTRACT TRUNCATED AT 250 WORDS)