In the first of these repeat studies (experiment 3, Table 1), the only significant weight change observed was an increase in the weight of the Cowper's glands at 5 [micro]g/kg/day FIN.
The control prostate weights showed the highest variability between experiments, as follows: prostate, 11%; Cowper's glands, 6%; seminal vesicles, 5%; glans penis, 4%; LMBC, 4%; liver, 1.
In this phase, a standardized protocol using ventral prostate, seminal vesicles with coagulating glands, levator ani and bulbocavernosus muscle complex, Cowper's glands, and glans penis was successfully tested against a reference androgen compound, testosterone propionate (TP), and a reference antagonist, flutamide (OECD 2001).
One laboratory (Lab 4) weighed the prostate, seminal vesicle, Cowper's glands, and adrenal glands after approximately 24 hr fixation in 10% formalin solution, following the procedure of Yamada et al.
For the Cowper's glands, the normalized dose-response curves produced by the four laboratories were similar, and the weight change ranged from 273% to 417% at 50 mg/kg/day MT relative to the vehicle control.