Establishing Standards for Studying Renal Function in Mice through Measurements of Body Size-Adjusted Creatinine and Urea Levels
Influence of thawing on the measurement of plasma urea concentration. Blood was obtained from C57BL/6 mice for measurement of plasma urea. After centrifugation, the plasma was separated into tubes and frozen at −20°C for 4 days, followed by thawing and measurement of plasma urea by spectrophotometry. Samples were then again frozen at −20°C for 86 more days, when plasma urea was again evaluated. Values are expressed in mg/dL; () statistically significant differences at .