Figure 37-10 Analysis of an externally monitored radioactive krypton washout curve for the kidney in a dog. Notice the logarithmic vertical scale. The rapid component (I) represents cortical blood flow. Half-times for each component together with estimated flow rates and compartment sizes are shown in the table above the plotted curves. (From Thorburn GD, Kopald HH, Herd A, et al: Intrarenal distribution of nutrient blood flow determined by krypton 85 in the unanesthetized dog. Circ Res 13:290, 1963.)