Cavett W, Tucci M, Cason Z, Lemos L, England B, Tsao A, Benghuzzi H
University of Mississippi Medical Center, Jackson 39216, USA.
Biomed Sci Instrum. 1997;33:155-60.
The objective of this study was to evaluate the effect of various dosages of testosterone (T) delivered in a sustained manner by means of tricalcium phosphate-lysine (TCPL) delivery system on morphological changes of prostatic tissue using adult male rats as a model. In this experiment, adult male rats (250-300 g BW) were randomly divided into five equal groups (n = 8). Rats in group I, II, and III were castrated and implanted subcutaneously with TCPL loaded with three different dosages (10, 100 and 200 mg T, respectively) of T. Rats in group IV were castrated and implanted with sharm TCPL capsules, and rats in group V served as intact unimplanted controls. Surgical aseptic techniques were performed according to standard laboratory procedures. At the end of 4 and 12 weeks post implantation, four animals from each group were sacrificed and the prostate tissues were collected, weighted, and embedded for histo-pathological evaluations. Data collected from this study have shown that exogenous intake of T delivered in a sustained manner for twelve weeks induced several pathophysiological conditions in ventral prostatic tissue in comparison to the control and sham operated groups. This phenomenon was found to be directly proportional to the dose or the level of sustained delivery. The results demonstrated that the use of 10 mg filled TCPL implants decreased the total mass weight of ventral prostate. Light microscopic evaluation of this group (Group I) revealed a cellular adaptation through an atrophy in the epithelium component. Cytopathological observations such as low cuboidal and thin glands, pleomorphism, and occasional presence of connective tissue stroma were detected. In contrast, ventral prostate collected from animals implanted with TCPL filled with 200 mg T (Group III) showed a significant increase in weights of the wet prostatic tissues in comparison to all groups. Histopathological evaluations demonstrated the following. (i) prostatic hypertrophy alone, or in conjunction with hyperplasia of the epithelial cells, (ii) less connective tissue stroma in comparison to the control group, (iii) occasional involvement of mitotic figures, and (iv) increased angiogenesis. No significant change was observed in those animals implanted with TCPL capsules containing 100 mg T compared to the intact control animals.
本研究的目的是，以成年雄性大鼠为模型，评估通过磷酸三钙-赖氨酸（TCPL）递送系统持续递送不同剂量睾酮（T）对前列腺组织形态变化的影响。在本实验中，成年雄性大鼠（体重250 - 300克）被随机分为五组，每组8只。第一组、第二组和第三组大鼠被阉割，并皮下植入分别装载三种不同剂量（10毫克、100毫克和200毫克T）T的TCPL。第四组大鼠被阉割并植入空的TCPL胶囊，第五组大鼠作为完整未植入的对照。按照标准实验室程序进行手术无菌操作。植入后4周和12周结束时，每组处死4只动物，收集前列腺组织，称重，并进行组织病理学评估。本研究收集的数据表明，与对照组和假手术组相比，持续12周外源性摄入T会在腹侧前列腺组织中引发多种病理生理状况。发现这种现象与剂量或持续递送水平成正比。结果表明，使用填充10毫克T的TCPL植入物会降低腹侧前列腺的总重量。对该组（第一组）的光镜评估显示，上皮成分萎缩导致细胞适应性变化。检测到细胞病理学观察结果，如低立方上皮和细腺体、多形性以及偶尔出现的结缔组织基质。相比之下，从植入填充200毫克T的TCPL的动物（第三组）收集的腹侧前列腺，与所有组相比，湿前列腺组织重量显著增加。组织病理学评估显示如下情况：（i）单独的前列腺肥大，或伴有上皮细胞增生；（ii）与对照组相比，结缔组织基质较少；（iii）偶尔出现有丝分裂象；（iv）血管生成增加。与完整对照动物相比，植入含100毫克T的TCPL胶囊的动物未观察到显著变化。
