INHIBITION OF AUTOPHAGY OF FETAL RABBIT GONODUCTS BY PUROMYCIN, TUNICAMYCIN AND CHLOROQUIN IN ORGAN-CULTURE

At the end of ambisexual stage, mullerian or wolffian ducts are progra mmed to die. Cell degeneration is initialized by an appearance of lyso somes, subsequently involved in invading autophagic vacuoles. In an or gan culture assay, performed for 6 days, treatments by puromycin, tuni camycin and chloroquine, known to act on synthesis, transport and acti vation of lysosomal enzymes, were applied to inhibit the duct regressi on. Four situations were studied: female genital tract of 17 day post coitum (d.p.c.) cultured with differentiated testis of 19 d.p.c.; male genital ducts of 17 d.p.c. cultured without testis; female and male g enital tracts of 17 d.p.c. cultured alone as controls. The stabilizati on of the mullerian duct cultured with testis and of the wolffian duct cultured without testis was obtained. Ultrastructuraly, the lysosomes were scarce or absent and no autophagic vacuoles were observed. In pr eventing the formation of lysosomes, it was possible to avoid the duct cell autophagy and to comfirm the existence of a wolffian lysosomal s ystem spontaneously active when testosterone is absent, while a muller ian one spontaneously inactive when AMH is absent.