[Biliary excretion of diethyl lead after administration of tetraethyl lead in rabbits].

In order to investigate into whether the large amount of inorganic lead excreted into the feces following intravenous injection of tetraethyl lead to rabbits is derived from the diethyl lead excreted into the bile, we administered 12 mg/kg of tetraethyl lead to rabbits which had been fistulated into the bile duct for taking the bile out of the body. The total lead excreted into the bile during the first 24 hours after the injection of tetraethyl lead amounted to about 8% of the injected amount of lead (with 97% of the excreted lead made up of diethyl lead). The amount of total lead contained in the cecal contents of unfistulated rabbits 24 hours after the injection of tetraethyl lead was equivalent to about 12% of the injected amount of lead (with inorganic lead accounting for about 90% of the excreted lead), but the counterpart of the fistulated rabbits was equivalent only to about 0.6%. The amount of lead excreted into the bile, when measured in terms of the total lead content of the liver, was slightly less in the fistulated rabbits than in the unfistulated ones. These findings indicated that the amount of total lead excreted into the bile of the fistulated rabbits was almost the same as that contained in the cecal contents of unfistulated rabbits, and that the major portion of the lead contained in the cecal contents or feces was composed of inorganic lead. From these results, we came to the conclusion that the large amount of inorganic lead detected in the feces after the injection of tetraethyl lead is derived from the diethyl lead excreted into the bile.