title: Ecdysteroids in developing ovaries and eggs of the tobacco hornworm.
abstract: Ecdysteroids of ovaries and newly-laid eggs (0- to 1-hour-old) of the tobacco hornworm are present mainly as conjugates (greater than 95%). Newly-laid eggs contain ecdysteroid conjugates equivalent to 21 micrograms of 26-hydroxyecdysone and 0.73 micrograms of ecdysone per gram of eggs. These levels are similar in ovaries of 93-hour-old adult females. In 1- to 18-hour-old eggs more than 63% of the ecdysteroids exist in the free form and the proportion is similar in 48- to 64-hour-old eggs. The ratio of 26-hydroxyecdysone to ecdysone in the conjugated form remains constant during oocyte maturation and embryogenesis. Though 26-hydroxyecdysone is without molting hormone activity in the house fly assay, the exceptionally high concentration of 26-hydroxyecdysone conjugate(s) in ovaries and newly-laid eggs, together with the fact that it is being released during embryogenesis, indicate some physiological role for 26-hydroxyecdysone.
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D026461:Ecdysteroids; D005260:Female; D005966:Glucuronidase; D006868:Hydrolysis; D007447:Invertebrate Hormones / Q000032:analysis*; D007915:Lepidoptera / Q000502:physiology*; D009036:Moths / Q000502:physiology*; D010053:Ovary / Q000254:growth & development*; D010063:Ovum / Q000502:physiology*; D001617:beta-Glucosidase
chemical_list: D026461:Ecdysteroids; D007447:Invertebrate Hormones; D001617:beta-Glucosidase; D005966:Glucuronidase