The stimulating effect of the Dorsal-Body Hormone on cell differentiation in the female accessory sex organs of the hermaphrodite freshwater snail, Lymnaea stagnalis

Abstract

An experimental study has been made on the role of the Dorsal Body Hormone (DBH) of the Dorsal Bodies (DB), of the growth hormone of the neurosecretory Light Green Cells (LGC) of the cerebral ganglia, and of the differentiation of the various secretory cell types in the accessory sex organs (ASO) of the hermaphrodite freshwater pulmonate snail L. stagnalis. To study this problem, undifferentiated rudiments of the ASO of juvenile snails were transplanted into the haemocoel of the head sinus of adult acceptors subjected to various types of operations. After 6 weeks the male and female ASO of sham-operated control acceptor snails showed clear signs of differentiation. The female ASO, with the exception of the ciliated groove, of DB or of DB + LGC cauterized acceptors had not differentiated. Reimplantation of DB or of DB + LGC stimulated the normal differentiation process. It is concluded that the cellular differentiation of the female ASO is controlled by the DBH. This hormone has no effect on the differentiation of the male ASO. The growth hormone of the LGC has no effect on the differentiation of either the female or the male ASO. Whether the differentiation of the male ASO is controlled by other endocrine centers remains to be studied.