RESORPTION OF UNEMITTED GAMETES IN LITHOGNATHUS-MORMYRUS (SPARIDAE, TELEOSTEI) - A POSSIBLE SYNERGIC ACTION OF SOMATIC AND IMMUNE CELLS

The resorption of unemitted gametes during the post-spawning period of the male and female reproductive cycles in Lithognathus mormyrus was studied by histochemical, histological and cytological methods. The re sorption of residual spermatozoa involved the phagocytotic activity of Sertoli cells bounding the seminiferous cysts of spermatozoa, and tho se associated with spermatogonia lining the lobular lumen. Spermatozoa remaining in the sperm duct were phagocytozed by the lining epithelia l cells. Eosinophilic granulocytes and macrophages were identified in the vicinity of residual spermatozoa. The remnants of oocytes underwen t an atretic phenomenon in which follicle cells were firstly involved, inducing a progressive fragmentation of the oocyte cytoplasm. Subsequ ently, eosinophilic granulocytes invaded oocyte degenerative areas and clung to the remaining vitelline inclusions ensuring their biotransfo rmation into waste products (brown bodies). The analogy of the resorpt ion processes of both male and female unemitted gametes during the pos t-spawning period of natural reproductive cycle, involving first the e nveloping somatic cells and then immune cells, is emphasized.