Stimulation in vivo de l'androgène testiculaire par Phormone cérébrale chez l'Annelide Oligochète,Eisenia foetidaf.typica Sav./ STIMULATION OF TESTICULAR ANDROGEN IN VIVO BY CEREBRAL HORMONE IN THE OLIGOCHAETE ANNELID,EISENIA FOETIDAVAR.TYPICASAV.

Abstract

In sexually active Eisenia foetida, the simultaneous implantation of ganglia of the central nervous system, ovaries and testes showed that the cerebral hormone stimulated the production of testicular androgen and maintained spermatogenesis. These results confirm those previously obtained by in vitro culture. When cerebral ganglia (CG) were implanted at different levels in the earthworm (CG segment or segment 7, testicular or ovarian segment), the percentage of testes transformed into ovotestes varied from 5 to 9%. The testicular androgen released under the control of CG was then able to masculinize partially 17–28% of the ovaries. On the other hand, some ganglia of the ventral nerve cord, such as subesophageal ganglia or ganglia of male or female genital segments, had no stimulating endocrine action on secretion of testicular androgen and on maintenance of the spermatogenetic activity of the gonia. In the presence of these different ganglia, no masculinization of ovaries occurred, and the percentage of transformation of testes into ovotestes reached 29, 42 and 41%, respectively.