Bockrath J M, Lee C, Grayhack J T
Invest Urol. 1981 Nov;19(3):169-75.
Rates of 3H-leucine incorporation into and release from the ventral prostate during castration induced involution were studied in adult male rats. We measured the rate of 3H-leucine incorporation by incubating the prostatic tissue in medium 199 containing 3H-leucine at 37 C for 1 hour. The rate of radioactivity incorporated into the protein fraction was expressed as cpm mg of protein. This rate reduced linearly from Day 0 to Day 6 post castration. Subcutaneous implantation of a silastic capsule containing crystalline testosterone to castrated rats restored the rate of incorporation to that of sham operated rats. To study the rate of 3H-leucine release, 3H-leucine prepared in 0.9 per cent Na C1 solution was injected intravenously into rats 1 day before castration. The amount of radioactivity remaining in the protein fraction of the prostate, expressed as cpm per prostate, was measured at different intervals after castration or after sham operation. Radioactivity disappeared at a significantly faster rate in the prostate of castrated rats than in sham operated controls. Testosterone replacement to castrated rats delayed the rate of loss of radioactivity to a degree similar to that of sham operated rats. These findings indicate that the rapid rate of protein loss in the regressing prostate is the result of a combined action of an accelerated rate of protein degradation and a rate of protein synthesis. Testosterone administration reversed these patterns of protein metabolism.
在成年雄性大鼠中，研究了去势诱导退化过程中腹侧前列腺对³H-亮氨酸的摄取率和释放率。我们通过将前列腺组织在含有³H-亮氨酸的199培养基中于37℃孵育1小时来测量³H-亮氨酸的摄取率。掺入蛋白质部分的放射性率以每毫克蛋白质的cpm表示。该率在去势后第0天至第6天呈线性下降。给去势大鼠皮下植入含结晶睾酮的硅橡胶胶囊可使摄取率恢复到假手术大鼠的水平。为了研究³H-亮氨酸的释放率，在去势前1天将溶于0.9%氯化钠溶液的³H-亮氨酸静脉注射到大鼠体内。在去势或假手术后的不同时间间隔测量前列腺蛋白质部分中剩余的放射性量，以每个前列腺的cpm表示。去势大鼠前列腺中的放射性消失速度明显快于假手术对照组。给去势大鼠补充睾酮可将放射性损失率延迟到与假手术大鼠相似的程度。这些发现表明，退化前列腺中蛋白质快速流失是蛋白质降解加速和蛋白质合成率共同作用的结果。给予睾酮可逆转这些蛋白质代谢模式。
