CHANGES OF NUTRITIONAL RESOURCES IN OVARIAN TISSUE OF DIPETALOGASTER MAXIMA DURING THE REPRODUCTIVE CYCLE

LEYRIA JIMENA; FRUTTERO LEONARDO; AGUIRRE SILVINA; RUBIOLO EDILBERTO; CANAVOSO LILIÁN

La Falda, Córdoba

Jornada; XIX Annual Scientific Meeting; 2013

SOCIEDAD DE BIOLOGÍA DE CÓRDOBA

In hematophagous insects, each gonadotrophic cycle is strongly associated with the intake of a blood meal, which must be appropriated in quantity and quality of nutrients to promote vitellogenesis. Under unfavourable nutritional conditions, there are changes in ovarian tissue that promotes follicular atresia and the utilization or redistribution of stored nutrients. In this study, we have analyzed the changes of the ovarian nutritional resources in the hematophagous Dipetalogaster maxima at pre-vitellogenesis, vitellogenesis and fasting-induced early and late atresia (post-vitellogenesis). The amounts of ovarian lipids, proteins and glycogen increased significantly from pre-vitellogenesis to vitellogenesis and then, diminished during atresia. Specific lipid staining of ovarian tissue sections evidenced remarkable changes in the shape, size and distribution of lipid droplets throughout the reproductive cycle. Cellular approaches demonstrated that lipid delivery to oocytes occurred at all reproductive stages, privileging the non-endocytic pathway of this lipoprotein during the stage of follicle degeneration. Altogether, the results indicated that in females, nutritional deprivation during post-vitellonesis is relevant in the progression of follicular atresia to either, facilitate insect lifespam or sustain the energetic demand of another gonotrophic cycle.