Immunoreactivity of the hermaphroditic gonad of the snail Helix aspersa M�ller towards antibodies raised to fragments of pre-pro-opio-melanocortin

Abstract

Male and female germinal cells of the active hermaphroditic gonad of a snail (Helix aspersa Muller) reveal a positive immunoreactivity to some antibodies raised against biologically active peptides related to pre-pro-opiomelanocortin of vertebrates. All but the oldest cells of the different spermatogenetic and oogenetic stages are methionine-enkephalin-immunopositive, whereas only the young oocytes are α-MSH- and 17–39 ACTH-positive. Sometimes some male cells show an 1–24 ACTH positivity. Structures other than germinal cells also react with some antibodies: for example, the nurse cells are β-MSH-immunoreactive, the nerve fibers surrounding each acinus and the hermaphrodite duct are both 17–39 ACTH and FMRF amide positive.