The presence and specificity of crustacean cardioactive peptide (CCAP)-immunoreactivity in gastropod neurons

CCAP-like immunoreactivity was detected in central neurons with small and m edium diameters in both Helix and Lymnaea CNS. The intensity of immunoreact ivity showed seasonal changes with a maximum intensity during spring. The o verwhelming majority of nerve cell bodies exhibiting CCAP immunoreactivity is located in the cerebral and parietal ganglia of both Helix and Lymnaea. The neurons of pleural and buccal ganglia were devoid of CCAP-immunoreactiv ity. Following preabsorbtion of CCAP antibody in 1:15000 dilution with 10(- 3) M CCAP or CCAP-related peptide (Helix -CCAP), immunoreactivity could not be observed in neurons, demonstrating the specificity of the antibody to C CAP-related molecules in both Helix and Lymnaea.