Quantification of antiandrogen effect determined by Lightcycler technology

During the last decade, the possible effects of xenobiotics on male reprodu ctive health have resulted in great concern. More recently. evidence of ant iandrogen effect in vivo by certain chemicals has been reported. The classi cal Hershberger in vivo assay determining organ weight changes can be impro ved by measuring hormone levels as well as determining changes in gene expr ession of androgen-responsive genes. A real-time RT-PCR method using LightC ycler technology (Roche) suitable for quantitative determination of gene ex pression is described. The technique combines rapid thermocycling with onli ne fluorescence detection of PCR product formation. In this study, investig ation of expression of prostate specific binding protein polypeptide C3 (PB P C3) and testosterone-repressed prostatic message 2 (TRPM-2) in the ventra l prostate was performed in 60-days-old castrated Wistar rats treated daily with testosterone with or without addition of flutamide or vinclozolin for 7 days in total. We show that we can quantify the level of gene expression by use of LightCycler technology, supported by changes in reproductive org an weights as well as in hormone levels, and that analysis of gene expressi on levels is an even more sensitive endpoint. (C) 2001 Elsevier Science Ire land Ltd. All rights reserved.