Nambirajan L, Agarwala S, Dinda A K, Mitra D K
Department of Pediatric Surgery, All India Institute of Medical Sciences, New Delhi-110029, India.
Pediatr Surg Int. 2002 May;18(4):276-80. doi: 10.1007/s003830100684.
Fertility is decreased in rats with experimentally-created unilateral undescended testis (UUDT). Although light microscopy has shown changes in the UDT, it has consistently failed to demonstrate any significant damage in the contralateral descended testis (CDT) of these animals in previous experimental studies utilizing the same model. To study the ultrastructural details of the CDT and the ipsilateral UDT using transmission electron microscopy (TEM) in rats with experimentally-created UUDT, in Wistar albino rat pups UUDT was experimentally created in accordance with the model described previously. Ten rats with UUDT were compared with 10 control rats. The UDT and CDT were harvested at 135 days of age and sections from specimens studied by TEM for changes in the seminiferous tubules, Leydig cells, and extracellular matrix. All observations were graded and analyzed for statistical significance. TEM of the testes of control rats was normal, while both the ipsilateral UDT and the CDT showed significant changes. Significant changes in the CDT included thickening of the basement membrane ( P=0.001), a decrease in spermatogenic cell lines ( P=0.02), vacuolation ( P=0.0001) and other features of degeneration ( P=0.02), single cell apoptotic figures ( P=0.02), and an increase in Sertoli-cell numbers ( P=0.01), size ( P=0.01), and endoplasmic reticulum ( P=0.01). Another significant feature was the occurrence of morphologic sperm abnormalities in the form of tail denudation ( P=0.02). The surgically-created UDT showed changes of gross degeneration and atrophy. TEM studies thus revealed gross ultrastructural damage to the UDT and similar subtle but significant changes in the CDT. These may explain the decrease in fertility in rats with UUDT.
在实验性单侧隐睾大鼠（UUDT）中生育能力下降。尽管光学显微镜已显示出隐睾存在变化，但在以往使用相同模型的实验研究中，始终未能证明这些动物的对侧下降睾丸（CDT）有任何明显损伤。为了利用透射电子显微镜（TEM）研究实验性UUDT大鼠中CDT和同侧隐睾的超微结构细节，在Wistar白化病幼鼠中按照先前描述的模型实验性制造了UUDT。将10只UUDT大鼠与10只对照大鼠进行比较。在135日龄时采集隐睾和CDT，并通过TEM对标本切片进行研究，观察生精小管、Leydig细胞和细胞外基质的变化。对所有观察结果进行分级并分析其统计学意义。对照大鼠睾丸的TEM检查正常，而同侧隐睾和CDT均显示出明显变化。CDT的显著变化包括基底膜增厚（P = 0.001）、生精细胞系减少（P = 0.02）、空泡化（P = 0.0001）和其他退变特征（P = 0.02）、单细胞凋亡图像（P = 0.02）以及支持细胞数量增加（P = 0.01）、大小增加（P = 0.01）和内质网增加（P = 0.01）。另一个显著特征是以尾部剥脱形式出现的形态学精子异常（P = 0.02）。手术制造的隐睾显示出明显的退变和萎缩变化。因此，TEM研究揭示了隐睾的严重超微结构损伤以及CDT中类似的细微但显著的变化。这些可能解释了UUDT大鼠生育能力下降的原因。
