Androgen and collagen as growth regulators of the rat ventral prostate

Abstract

With the aim of studying a possible role of the fibromuscular stroma as growth regulator for the rat ventral prostate the weight, DNA content, and hydroxyproline content were analyzed in the ventral prostate of rats of varying age. Exogenous androgen increased the age-dependent weight and contents only in young and old rats. Orchiectomy reduced prostatic weight, DNA content, and hydroxyproline content although to different extent, and exogenous androgen restored the weight and contents. Exogenous estrogen to intact animals had effects similar to orchiectomy. Estrogen combined with androgen increased DNA content over that found in animals given androgen only, while weight and hydroxyproline content were not changed. It is concluded that the endogenous androgen determines the size of the prostate in young and old animals. Androgen also determines prostatic collagen content. The good correlation between prostatic DNA and hydroxyproline indicates a more or less fixed number of epithelial cells per amount of collagen. A hypothesis suggesting a crucial role for prostatic collagen in the growth-limiting mechanism in the prostate is presented.

Alteration of Collagen Biosynthesis and Analysis of Type I and Type III Collagens of Prostate in Young Rats Following Sex Hormone Treatments

“…He suggested a crucial role for prostatic collagen growth-limiting factor [12]. In our study, testosterone treatment failed to alter the chemical composition of type I and 111 collagens in rat ventral prostate.…”

“…According to Muntzing [12], endogenous androgen determines the size of the prostate in young and old animals. He suggested a crucial role for prostatic collagen growth-limiting factor [12].…”

Effects of Mesenchyme of the Embryonic Urogenital Sinus and Neonatal Seminal Vesicle on the Cytodifferentiation of the Dunning Tumor: Ultrastructural Study

“…54], Synthe sis and accumulation of collagen in the prostate is regulated by androgens and estrogens [53][54][55][56], In our present combi nation studies epithelial cytodifferentiation in DT-derived tubules is correlated with an increase in the amount of collagen fibers which may come from two sources: the mes enchyme (UGM or SVM) or from the DT stromal fibro blasts. Embedded in the stromal matrix of the UGM + DT are fibroblasts, a small number of epithelioid cells as described by Beckman et al [3] and smooth muscle cells.…”

Androgen Receptor-Ets Protein Interaction Is a Novel Mechanism for Steroid Hormone-mediated Down-modulation of Matrix Metalloproteinase Expression

“…Androgens Down-regulate MMP Gene Expression-Increase in collagen expression by androgens has been suggested to occur from a negative action of the hormone on MMP gene expression (18,19). To verify this, we carried out Northern blot experiments with mRNA isolated from androgen receptor positive LNCaP cells previously treated with androgens and the phorbol ester TPA to enhance MMP expression.…”

“…The only link between androgens, their receptor, and MMPs is the finding that collagen content in ventral prostate of the rat is increased in the presence of androgens and decreased after orchiectomy. These results are partly interpreted as reflecting a negative effect of the AR on MMP expression (18,19). It however remains to be demonstrated which MMPs are involved and the mechanism by which this down-regulation of expression is brought about.…”