TY - JOUR TI - EFFECT OF AN ACUTE ORAL PROTEIN LOAD ON MICROALBUMINURIA IN UNINEPHRECTOMIZED PATIENTS IN RELATION TO THE TIME SINCE NEPHRECTOMY AU - PAPAGALANIS, N AU - GENNADIOU, M AU - KARABATSOS, A AU - KOSTOGIANNI, G and AU - PHENEKOS, C AU - ELISAF, M AU - KOURTI, A AU - ZACHAROF, A AU - SIAMOPOULOS, AU - K AU - MOUNTOKALAKIS, T JO - Nephron Extra PY - 1994 VL - 68 TODO - 2 SP - 169-179 PB - Karger SN - 1664-5529 TODO - 10.1159/000188252 TODO - MICROALBUMINURIA; PROTEIN LOADING; UNINEPHRECTOMIZED PATIENTS; RENAL FUNCTION TODO - To evaluate the effect of an acute oral protein lend (OPL) on urinary albumin excretion (UAE) in uninephrectomized subjects with a negative Albustix test, in relation to the time since nephrectomy. the UAE was determined by a double-antibody I-125 radioimmunoassay in 3-hour urine collections before and after 150 g OPL under conditions of moderate physical activity in 18 subjects who underwent unilateral nephrectomy more than 10 years (346.5+/-178.60 months) before evaluation and had a mean basal creatinine clearance (C-Cr) of 45.3+/-14 ml/min (group 1), in 21 subjects who under went unilateral nephrectomy less than 10 years (31.5+/-28 months) before evaluation and had a mean basal C-Cr of 76.0+/-22 ml/min (group 2), and in 16 normal volunteers (controls) with a mean basal C-Cr of 103.1+/-12 ml/min. The UAE was higher in group 1 as compared with either group 2 or controls at both basal state (90.8+/-65, 19.6+/-17, and 11.0+/-5 mu g/min/100 C-Cr for groups 1 and 2 and controls, respectively; p<0.001) and after OPL (92.0+/-65, 43.6+/-24, and 12.0+/-5 mu/min/100 C-Cr for groups 1 and 2 and controls, respectively; p<0.001). However, the increase in UAE following OPL was significant (p<0.001) only in group 2 patients. In all patients, the basal UAE was negatively correlated with basal C-Cr (r=0.63; p<0.001) and positively correlated with the time since nephrectomy (r=0.73; p<0.001) and with both systolic (r=0.57; p<0.001) and diastolic blood pressures (r=0.69; p<0.001). Ca calculated using 3-hour urine collections increased more in controls (11.2+/-44.2%) than in patient groups 1 (1.6+/-0.89) and 3 (7.7+/-3.7%; p<0.001). Basal C-Cr calculated using 24-hour urine collections the day before the test was negatively correlated with the time since nephrectomy in group 1 (r=-0.69; p<0.001) and positively correlated with the time since nephrectomy in group 2 (r=0.89; p<0.001). Multiple regression analysis revealed that the relationship between C-Cr and duration of uninephric state was independent of age or systolic and diastolic blood pressures in both patient groups. These results suggest that UAE increase significantly after an OPL in subjects who have been nephrectomized less than 10 years before the study and have basal C-Cr values higher than 50% of normal. They also suggest that the risk of developing renal insufficiency increases with time in subjects with a solitary kidney for more than 10 years; this increase in risk seems to follow a progressive compensatory increase in glomerular filtration rate of the remnant kidney during the early years following uninephrectomy. ER -