Renal hemodynamic calculation
mGFR and effective renal plasma flow (eRPF) will be calculated using inulin and PAH clearance, respectively. Briefly, 1% inulin and 0.5% PAH will be administered by means of a continuous intravenous infusion for 2 h under overnight fasting but hydrated conditions. If the participants are prescribed diabetic drugs and diuretics, they will be instructed to suspend the use of these drugs. Before infusion, participants will drink 500 ml of tap water in the outpatient treatment room to stimulate diuresis. During infusion, blood samples will be drawn 2 times at 45 and 105 min for measurement of serum levels of inulin and PAH, and urine samples will be collected between 45 and 105 min for measurement of urinary inulin and PAH excretion after completely emptying the bladder 45 min after the start of the infusion.The filtration fraction (FF), effective renal blood flow (eRBF), and renal vascular resistance (RVR) will be calculated by dividing mGFR by eRPF, eRPF by (1-hematocrit), and mean blood pressure by eRBF, respectively. eGFR from creatinine levels (eGFRcreat) will be calculated as follows: eGFRcreat (mL/min/1.73 m