Figure 37-6 The regulatory mechanisms through which glomerular filtration is modulated include (1) fractional regional blood flow (renal blood flow/cardiac output); (2) filtration fraction (glomerular filtration rate/glomerular plasma flow rate); and (3) fractional tubular fluid reabsorption (tubular reabsorption/glomerular filtration rate). (Adapted from Badr KF, Ichikawa I: Prerenal failure: A deleterious shift from renal compensation to decompensation. N Engl J Med 319:623, 1988.)