Blood clearance of 99mTc-phytate for evaluation of hepatic dysfunction in rats

Organ distribution pattern, hepatic uptake ratio, and blood clearance were examined by giving 99mTc-phytate (99mTc-P) to the normal rats. At the same time, the relation between the severity of hepatic function and blood clearance or hepatic uptake ratio of 99mTc-P was studied by using the rats with acute hepatic dysfunction experimentally induced by carbon tetrachloride (CCl4) administration. Furthermore, a comparative discussion on blood clearance test of 99mTc-P was made with serum transaminase test and with histological test of the liver. It appeared appropriate to administer 99mTc-P at the dose of 500 micrograms/kg in order to obtain an effective blood clearance curve. A major part of 99mTc-P intravenously administered was take up into the liver, while the remainder of small amount into the spleen, kidneys, lung, and so on. Little was recognized in the thyroid gland. The hepatic uptake ratio of 99mTc-P reached the maximum 15 minutes after the administration. The disappearance rate of 99mTc-P from blood decreased with the increase in dose of CCl4 and with the passage of time after the CCl4 administration. The blood clearance test of 99mTc-P showed a sensitive reaction for the acute hepatic dysfunction induced by CCl4 equally to or higher than the serum transaminase test or histological test of the liver.