ENDOCRINE AND NEUROENDOCRINE EFFECTS OF AZADIRACHTIN IN ADULT FEMALESOF THE EARWIG LABIDURA-RIPARIA

In previous studies we have shown that injection of the insect growth regulator Azadirachtin (AZA) into young vitellogenic females induces i nhibition of vitellogenesis in a dose-dependent manner, Juvenile hormo ne treatment rescues vitellogenin synthesis acid ovarian growth, The c ytopathological effects on ovaries and fat body are not linked to an i nhibition of feeding, In this work we investigated the effects of AZA on the endocrine and neuroendocrine system, Enzyme immunoassay reveals that ovarian ecdysteroid levels are drastically reduced, in a dose-de pendent fashion, by AZA, Ultrastructural study indicates that corpus a llatum cells exhibit signs of inactivity and degenerative changes afte r AZA exposure, Using an antibody against allastostatin-3 of Blatella germanica (BLAST-3), we show the appearance of strong immunoreactivity of numerous cells and axons in the brain of AZA-injected females. We conclude that vitellogenesis inhibition by AZA consists of a direct cy totoxic effect as well as a generalized disruption of endocrine and ne uroendocrine functions.