Immunofluorescent evidence of an FMRFamide-like peptide in the peripheral nervous system of the gastropod mollusc Helix aspersa.

An antiserum raised against the FMRFamide peptide revealed a highly developed peripheral nervous system in the mollusc Helix aspersa. Immunoreactive fibres associated with muscular fibres are observed in all organs. Cell bodies are frequently seen, for example in the digestive and genital tracts. The antiserum also revealed associations between immunoreactive fibres and non-reactive perikarya. In Helix aspersa an FMRFamide-like peptide is most likely a neurotransmitter/neuromodulator for muscular and peripheral nervous activity.