Compartmental studies of a mouse brain tumor

The purpose of this study was to determine the hematologic compartments, vascular, plasma, and extracellular fluid volumes of a brain tumor, normal brain, and other tissues in a well established mouse brain tumor model. Tumor vascular volume, determined using Cr-51 labeled red blood cells, was found to be 0.019 ml/g tumor over the first hour. Plasma volumes were estimated using I-131 labeled albumin. Only the 10-minute value (when corrected by the plasmacrit, 0.497) of 0.019 ml/g tumor agreed with the vascular volume. Extracellular fluid space, measured using 35S sulfate, was found to be 0.51 ml/g tumor after an equilibration time of 6 hours. Relatively constant compartmental space values were obtained for other tissues except liver