ALUMINIUM CHLORIDE INDUCES ALTERATIONS IN THE MUCINS SECRETED BY THE TERRESTRIAL SNAIL, EOBANIA VERMICULATA

Aluminium, widely present in daily life1, is reported to be linked to several neurological disorders. We evaluated the effects of AlCl3 on the terrestrial snail Eobania vermiculata, an excellent bioindicator of soil pollutants. Histochemical and lectin histo-chemical techniques were used to investigate glycopattern variation in the mucins secreted by the pedal glandular system,involved in several functions, such as adhesion, locomotion, and protection. Three groups of adult snails (mean shell size = 2.5cm; mean weight = 4.6 g) were fed daily with 4 g of lettuce soaked in a AlCl3 water solution at three different concentrations(0, 50, and 200 μM). After 30 days, animals were sacrificed, Bouin-fixed and embedded in paraffin. Sections, 6- m thick, were analysed by histochemical methods (PAS, AB pH 2.5, HID-ABpH 2.5) and lectin binding experiments (PNA, SBA, WGA, LTA,UEA-I, AAA, SNA, MAA II, ConA). Controls were positive toPAS, AB pH 2.5, and with HID stained mostly brown, indicatingthe presence of carboxylated and sulphated glycans. Positivity was reduced in the treated snails, where the secretion was con-centrated in the gland ducts rather than in the adenomeres. ConA(linking to mannosylated and/or glycosylated residuals) bound strongly to all the samples both in the dorsal area and the sole.SBA and WGA (linking to galactosaminylated and glycosaminy-lated/sialylated residuals, respectively) increased their binding in the dorsal area of the foot of treatments. AAA, linking to fuco-sylated residuals, decreased its binding in the treatments. In the sole, SBA-binding decreased in the treatments. In conclusion, the AlCl3 treatment affects the quali-quantitative expression of gly-cans in the foot. Physiopathological implications of changes will be investigated in further research.