TISSUE DISTRIBUTION OF THE SALMFAMIDE NEUROPEPTIDES S1 AND S2 IN THE STARFISH ASTERIAS-RUBENS USING NOVEL MONOCLONAL AND POLYCLONAL ANTIBODIES .2. DIGESTIVE-SYSTEM

Specific monoclonal and polyclonal antisera raised against the starfis h SALMFamide peptides S1 and S2: have been used to determine the tissu e distribution and cellular localization of these novel neuropeptides in the starfish Asterias rubens. The present study examines the digest ive system of this animal using single-and double-labelling optical im munocytochemistry (Ice). The results reveal a widespread neuronal loca lization for S2 to axons and perikarya throughout the digestive system . Double-labelling revealed a predominantly separate localization for S1 and S2 immunoreactivity. This distribution, in conjunction with pre vious pharmacological studies implicate a role for this peptide in gut relaxation.