Renal clearance of [14C]oxalate: comparison of constant-infusion with single-injection techniques.
1. The renal clearance of [14C]oxalate was assessed by the constant-infusion technique and single-injection technique (plasma sampling only: one-compartment and two-compartment model; plasma and urine sampling). Healthy volunteers and patients with renal stones were studied. 2. Results with the constant-infusion techniques (with and without urine sampling) were not significantly different from each other. 3. The renal clearance of [14C]oxalate measured with the single-injection technique as compared with the constant-infusion technique was overestimated in the single-injection one-compartment model (52%) as well as in the two-compartment model (30%). 4. The calculated level of plasma oxalate in the healthy volunteers ranged from 1.04 to 1.78 mumol/l (mean 1.39). 5. The biological half-life of [14C]oxalate, estimated by the cumulative excretion of 14C in urine after equilibrium had been established, was 128 min (range: 113-142). 6. The oxalate/creatinine clearance ratio in the healthy volunteers ranged from 1.73 to 2.22 (mean 2.01).
D005260:Female; D006207:Half-Life; D006801:Humans; D007263:Infusions, Parenteral; D007275:Injections, Intravenous; D007668:Kidney / Q000378:metabolism*; D007669:Kidney Calculi / Q000378:metabolism; D008297:Male; D008657:Metabolic Clearance Rate; D010070:Oxalates / Q000008:administration & dosage / Q000378:metabolism*; D019815:Oxalic Acid
D010070:Oxalates; D019815:Oxalic Acid