If it yielded significant differences, the differences between the vehicle control group and each of the MT groups or the positive control group and each of the VCZ and p,p'-DDE groups were analyzed by Dunnett's test.
No significant differences in body weight were observed between the positive control group that received TP injections alone and the VCZ group in any of the laboratories.
The ventral prostate weight changes at 100 mg/kg/day VCZ relative to the positive control ranged from 27% to 37%.
For the BC/LA, the normalized dose-response curves produced by the four laboratories were similar, and the weight change at 100 mg/kg/day VCZ relative to the positive control were similar, ranging from 48% to 52%.
The normalized dose-response curves produced by the four laboratories were similar for the glans penis, and the weight change at 100 mg/kg/day VCZ relative to the positive control were similar, ranging from 69% to 73%.
The weight change ranged from 36% to 42% at a dose of 100 mg/kg/day VCZ relative to the positive control.
The weights of all the accessory sex organs from the experimental animals in all the laboratories exhibited significant dose-related changes in the assays using agonistic MT or antagonistic VCZ and p,p'-DDE; the normalized dose-response curves showed that all five tissues reacted in a similar manner for each compound.
In the present study, it was difficult to select a particularly sensitive organ from among the five tissues examined in the androgen agonistic MT and antagonistic VCZ and p,p'-DDE assays.
In the assay using the androgen antagonistic chemicals, slight differences in the normalized response curves for low doses in the p,p'-DDE assay were observed among the laboratories, but the response curves for each organ in the VCZ assay were similar.