Imaginal disc bioassay

Table 3 Imaginal disc bioassays, giving the concentration of ecdysteroid required for 50% evagination (EC50) and the IC50 or Kd value determined from a competion assay for specifically bound [3H]ponasterone A.

The evagination of imaginal discs of Dipteran and Lepidopteran insects is a well-characterised ecdysteroid-dependent system, which has been used by several authors to develop bioassays [183-187], However, they have been used to only a limited extent to compare the biological activities of ecdysteroids (Table 3 ). 

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