Institute of Biology, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil.
Microsc Res Tech. 2011 Nov;74(11):1040-8. doi: 10.1002/jemt.20991. Epub 2011 Apr 20.
We investigated the impact of diabetes with simultaneous and late insulin replacement on rat prostate growth during puberty, paying special attention to different prostatic lobes. Diabetes was induced by administration of streptozotocin (STZ) in 40-day-old male Wistar rats. A subset of diabetic rats underwent simultaneous insulin replacement (3 days after STZ administration), and another subset underwent a late insulin replacement (20 days after STZ administration). The ventral, dorsolateral, and anterior prostatic lobes were weighed and processed for histological, immunohistochemical, and morphometric analyses. Both diabetic and insulin-treated animals maintained low plasma testosterone (T) concentrations, whereas dihydrotestostenore (DHT) levels were normal. Diabetic animals had a decreased gain in absolute prostatic weight when compared to age-matched controls and insulin replacement animals. However, prostatic lobe weight in the diabetic animals was ∼100% higher, even at the beginning of the experiment. Among the lobes, the anterior lobe showed the highest weight gain in diabetic and insulin replacement conditions. Epithelial cell proliferation in all lobes was significantly reduced in diabetic animals and significantly increased in insulin replacement animals, although apoptosis was unaltered. In conclusion, diabetes diminishes, but does not abolish, prostate growth during puberty. Even late insulin administration reduces the adverse effects of this disease on the prostate. In a scenario with both low insulin and T levels, DHT and other factors may play an important role in pubertal prostate growth. The adverse effects of diabetes on the rat prostate show a variation in lobe response, suggesting that diabetes may affect human prostate zones differently.
我们研究了糖尿病同时和后期胰岛素替代对青春期大鼠前列腺生长的影响，特别关注不同的前列腺叶。糖尿病通过链脲佐菌素（STZ）在 40 天大的雄性 Wistar 大鼠中诱导。一部分糖尿病大鼠进行同时胰岛素替代（STZ 给药后 3 天），另一部分进行晚期胰岛素替代（STZ 给药后 20 天）。对腹侧、背外侧和前叶前列腺进行称重，并进行组织学、免疫组织化学和形态计量学分析。糖尿病和胰岛素治疗的动物均保持低血浆睾酮（T）浓度，而二氢睾酮（DHT）水平正常。与年龄匹配的对照组和胰岛素替代动物相比，糖尿病动物的前列腺绝对重量增加减少。然而，即使在实验开始时，糖尿病动物的前列腺叶重量也增加了约 100%。在所有叶中，前叶在糖尿病和胰岛素替代条件下显示出最高的重量增加。所有叶的上皮细胞增殖在糖尿病动物中显著减少，在胰岛素替代动物中显著增加，尽管细胞凋亡未改变。总之，糖尿病在青春期会抑制前列腺生长，但不会完全阻止。即使晚期胰岛素给药也会减少这种疾病对前列腺的不良影响。在胰岛素和 T 水平均低的情况下，DHT 和其他因素可能在青春期前列腺生长中发挥重要作用。糖尿病对大鼠前列腺的不良影响显示出叶反应的变化，这表明糖尿病可能以不同的方式影响人类前列腺区。
