Rouleau M, Léger J, Tenniswood M
Department of Biochemistry, University of Ottawa, Ontario, Canada.
Mol Endocrinol. 1990 Dec;4(12):2003-13. doi: 10.1210/mend-4-12-2003.
The rat ventral prostate is a complex gland composed of numerous ducts. The epithelial cells that line the lumen of the ducts are surrounded by stromal cells. The epithelial cells display a characteristic morphology that is dependent on their anatomical location within the ducts; the cells that line the lumen in the region of the ducts close to the urethra (the proximal region) are cuboidal, while those in the distal regions of the ducts are tall columnar cells. We have examined the regional expression of two genes that are expressed in the prostate: prostate steroid-binding protein (PSBP; a marker for androgen-dependent protein synthesis) and TRPM-2 (a marker for programmed cell death). We have demonstrated that the expression of PSBP, in the presence of androgens, and TRPM-2, in the absence of androgens, is restricted to the luminal epithelial cells in the distal regions of the prostatic ducts. Neither of the genes is expressed in the proximal regions of the ducts. In view of the probable effects of the epithelial-stromal interactions in the gland we have also characterized the cytokeratin composition of the epithelial cells lining the prostatic ducts. We have established that the basal epithelial cells of the prostate are primarily localized in the proximal region of the ducts. We propose that these cells may attenuate the influence of the stromal cells on the luminal epithelium and exert a negative influence on the cytodifferentiation of the secretory epithelial cells. The results also suggest that PSBP, which has been considered to be an androgen-dependent gene may, in fact, be a sequence that is constitutively expressed in the luminal cells that die in the absence of androgens. This has significant implications on the mechanism of androgen action in the rat ventral prostate.
大鼠腹侧前列腺是一个由众多导管组成的复杂腺体。导管腔内衬的上皮细胞被基质细胞包围。上皮细胞呈现出依赖于其在导管内解剖位置的特征性形态；靠近尿道的导管区域（近端区域）腔内衬的细胞为立方形，而导管远端区域的细胞为高柱状。我们研究了在前列腺中表达的两个基因的区域表达情况：前列腺类固醇结合蛋白（PSBP；雄激素依赖性蛋白合成的标志物）和TRPM - 2（程序性细胞死亡的标志物）。我们已经证明，在雄激素存在的情况下PSBP的表达以及在雄激素缺乏的情况下TRPM - 2的表达仅限于前列腺导管远端区域的腔上皮细胞。这两个基因在导管的近端区域均不表达。鉴于腺体中上皮 - 基质相互作用的可能影响，我们还对前列腺导管内衬上皮细胞的细胞角蛋白组成进行了表征。我们已经确定前列腺的基底上皮细胞主要定位于导管的近端区域。我们提出这些细胞可能会减弱基质细胞对腔上皮的影响，并对分泌上皮细胞的细胞分化产生负面影响。结果还表明，一直被认为是雄激素依赖性基因的PSBP，实际上可能是在缺乏雄激素时死亡的腔细胞中组成性表达的序列。这对大鼠腹侧前列腺中雄激素作用的机制具有重要意义。
