Biliary Excretion of Lead in the Rat

Abstract

Studies have been made in the rat of the elimination of 210Pb in the bile after the intravenous injection of 100 μg. of lead. Four groups of rats were used: in two the bile was drained by cannulation of the bile duct, and in the other two the bile flow to the duodenum was interrupted by ligation or division of the bile duct. The radioactivity of the bile, of the intestinal walls, and of the intestinal contents and faeces was determined. The results showed that lead is eliminated from the liver mainly by the bile, thus excluding passage through the intestinal walls into the faeces as important under these conditions.

Biliary excretion of 203Hg, 64Cu, 52Mn, and 210Pb in the rat

“…In most investigations, either one route or the other has been studied, and often only on one metal. This is a reason for the discrepancies in estimates of the relative importance of the two routes (for example, for lead, Witschi (1964) and Castellino, Lamanna and Grieco (1965)). For mercury, most attention has so far been paid to excretion in urine because of the marked tendency of mercury to be excreted by this route (Friberg, 1956).…”

Interaction of L‐Ascorbic Acid on the Disposition of Lead in Rats

“…disposition and elimination of As-Ac in rats can be adequately described by linear or first-order processes. In addition, kidney and liver are known to play a major role in the elimination of lead (Goyer et al 1971;Goyer & Chirian 1979;Castellino et al 1966). The practical implication of this finding is that the steady state concentrations for As-Ac in rats will not be attained until 30 to 35 hr of continuous dosing.…”

“…The major manifestations of lead toxicity include haematological disorders, urinary excretion of gamma aminolevulinic acid and degenerative changes in the proximal tubule of kidneys (Friberg 1979;Boeckx 1986). In addition, kidney and liver are known to play a major role in the elimination of lead (Goyer et al 1971;Goyer & Chirian 1979;Castellino et al 1966). In view of these reports, femur, kidney, liver and plasma were included in the study investigating the effect of As-Ac on the disposition of lead in rats.…”

Susceptibility to Lead Toxicity

“…From experimental studies in dogs and rats it has been learned that lead is excreted from the liver mainly in bile (7,8). A portion of ingested lead may be absorbed from the upper gastro-intestinal tract, transported across liver cells and ex-creted into the gut by way of the biliary system.…”