Distribution of alpha CDCP-immunoreactive neurons in the central nervous system of the snail Helix aspersa.

alpha CDCP is a neuropeptide produced by the caudodorsal cells of Lymnaea stagnalis and encoded by the genes of the egg-laying hormone (ELH). The use of a polyclonal antiserum raised against alpha CDCP resulted in the detection of about 800 immunoreactive neurons in the parietal ganglia and a small population (60 cells) in the cerebral ganglia of Helix aspersa. As the genes of ELH are well conserved among the gastropod species, these data designate the parietal ganglia as a putative source for the egg-laying hormone in Helix aspersa.