Co-existence of immunoreactivity to anti-dopamine, anti-serotonin and anti-vasotocin in the cerebral giant neuron of the pond snail Lymnaea stagnalis.

Consecutive sections of certain neurons in the central ganglia of the pond snail Lymnaea stagnalis appear to be immunoreactive to anti-dopamine and anti-serotonin. The Cerebral Giant Neurons stain in addition with anti-vasotocin. The observations indicate the presence of two biogenic amines within the same neuron and in addition their co-existence with a biologically active peptide.