METABOLISM OF ECDYSONE AND 20-HYDROXYECDYSONE IN ADULT DROSOPHILA-MELANOGASTER

The metabolism of [H-3]ecdysone injected into adult female and male Dr osophila melanogaster was investigated. The metabolites present in fli es and faeces were analysed separately after incubation times of 1, 2 or 4 h. In female flies ecdysone-22-fatty acid acyl esters were the ma jor metabolites followed by 3-dehydroecdysone, 26-hydroxyecdysone, ecd ysonoic acid, 20-hydroxyecdysone and a negatively charged conjugate of ecdysone. In male flies the same compounds were formed, but their rel ative concentrations were somewhat different from those in female flie s. All metabolites formed can be excreted. [H-3]20-hydroxyecdysone was metabolized in much the same way: 20-hydroxyecdysone-22-acyl esters, 3-dehydro-20-hydroxyecdysone, 20-hydroxy-ecdysonoic acid and a negativ ely charged conjugate of 20-hydroxyecdysone were formed. However, 20,2 6-dihydroxyecdysone could not be detected after injection of [H-3]20-h ydroxyecdysone.