Shell thickening in Anodonta cygnea by TBTO treatments

Abstract

1. Low level TBTO (bis(tributyltin)oxide) treatments (0.2 μg/l) caused, in vivo, a secretion of a calcified organic matrix over the inner face of the shell of Anodonta cygnea after eight days. 2. Electrophysiological studies carried out on the outer mantle epithelium (OME) showed that the short-circuit current was strongly inhibited by TBTO from the shell side. On the contrary, the effect is very slow from the haemolymph side. 3. The TBTO effect on the proton and/or bicarbonate transport mechanisms across the OME can be a strong factor in the shell thickening.