Fast, effortless and accurate measurement of glomerular filtration rate in conscious monkeys

706 Objectives: The goal of this study is to evaluate an approach developed for humans to measure renal function in conscious rhesus monkeys with the accuracy of clearance techniques and the convenience of plasma creatinine. Methods: GFR was measured in two males and two females Rhesus monkeys following a continuous infusion of 125I-iothalamate or a single intravenous injection of 99mTc-DTPA. Continuous measurements of radioactivity from 99mTc-DTPA were performed with an external radiation detector rather than with intermittent and deferred assay of urine and venous blood. GFR was measured on day 1 under anesthesia using both techniques simultaneously. The 99mTc-DTPA study was repeated on days 8 and 45. Results: The properties of the technique including sensitivity, accuracy, precision and resolution time were determined and found adequate and greatly improved in comparison with standard clearance techniques. Conclusions: The method proposed represent a fast, accurate and convenient way to measure GFR in conscious monkeys.