Study of 131I-rose bengal kinetics in normal man: a critical evaluation of a three-compartment model

The plasma disappearance curve following a single intravenous injection of a tracer dose of 131I-labelled Rose Bengal (131I RB) is used to calculate the parameters of a three-compartmental model. In the model proposed, plasma 131I RB exchanges with two additional pools, one of which is thought to represent extrahepatic extravascular compartment (compartment 2) and the other the liver (compartment 3). 131I RB is assumed to be eliminated from the system solely from compartment 3 by secretion into bile, and no urinary excretion is taken into consideration. The assumptions implicit in the model (no excretion of 131 I RB in urine, reflux from liver to plasma, exchange with extravascular extraphepatic compartment, identification of compartments 2 and 3 respectively as extravascular extrahepatic, and intraphepatic) are supported by a set of experimental data.