Alteration in biogenic amine levels in the snail Lymnaea acuminata by the latex of Euphorbia royleana.

The latex of Euphorbia royleana which has high molluscicidal and anti-cholinesterase activity against Lymnaea acuminata reduced the levels of 5-hydroxytryptamine (5HT) and dopamine (DA) in the nervous tissue of L. acuminata. There was, however, no significant change in the level of 5-hydroxyindole acetic acid (5HIAA). The changes were found to be dependent on concentration of the latex extract. Similar changes were produced by both water and organic solvent extracts of the latex. The latex of E. royleana thus affects all the known neurotransmission mechanisms in the snail either separately or through a complex interaction between the different neurotransmitters. This may account for its high toxicity to snails.