Transient tenascin enhancement is an early event after androgen ablation in rat prostate

Tenascin (tenascin-C). a mesenchymal glycoprotein, is expressed in many tis sue remodeling processes. We evaluated tenascin expression during androgen- deprivation-related involution of the rat prostate. At set intervals follow ing castration and subsequent testosterone repletion, prostates were remove d in 30 Introduction adult rats. Each prostate was immunostained with a pol yclonal antiserum against rat tenascin and keratin antibodies specifically directed against exocrine basal cells and luminal cells in the prostate gla ndular structure. Morphologic impressions were semiquantatively evaluated u sing a computer-assisted image analysis system. Rat prostates showed a tran sient increase in the periglandular tenascin expression directly following castration that reached a maximum at day 3. At day 6, tenascin expression w as similar to control prostates. This was accompanied by a decrease of cell s in the luminal cell layer. The weakest tenascin immunoreactivity was note d on day 14 after androgen withdrawal. This process was reversed by androge n repletion. This study shows that in the rat prostate tenascin expression may be androgen dependent and that during androgen deprivation-related invo lution tenascin expression is probably associated with tissue remodeling by stromal-epithelial interactions.