Accumulation of 241Am in subcellular structures of the hepatopancreas of the lobster Homarus gammarus

Abstract

Some of the artificial radionuclides released by the nuclear industry are assimilated by marine organisms. In this study, an attempt is made to elucidate the detailed mechanisms of super(241)Am accumulation within the intracellular constituents of lobster (Homarus gammarus ) hepatopancreas; the experimental procedure involved contaminating lobsters with a radiolabelled meal. The monitoring of activity levels in the digestive gland shows that the intracellular incorporation of this radioisotope occurs through a 2-fold process of adsorption onto membranes coupled with endocytosis, taking place within 30 min of ingestion. The breakdown of exogenous ligands releases americium, which then appears to be distributed between subcellular structures via the mediation of a cytosolic vector. After 24 h, various cellular constituents are affected by autophagous processes which cause a reconcentration of super(241)Am into residual bodies