Matsuno Yoshiharu, Komiyama Masatoshi, Tobe Toyofusa, Toyota Naoji, Adachi Tetsuya, Mori Chisato
Departments of Bioenvironmental Medicine and.
Urology, Graduate School of Medicine, Chiba University, Chiba.
Reprod Med Biol. 2003 Sep 26;2(3):109-113. doi: 10.1046/j.1445-5781.2003.00026.x. eCollection 2003 Sep.
Previously, in cryptorchid rats, which were induced by prenatal exposure to flutamide, we found a thickening of the cremaster muscle. This study was undertaken to quantify the increase of the cremaster muscle thickness in the cryptorchid rats, and to examine its possible relationship with the proliferation of muscle cells. To obtain cryptorchid rats, pregnant Wistar rats were subcutaneously injected with flutamide (100 mg/kg per day) during gestational days 16-17. Serial sections of the scrotum, containing the testis and cremaster muscle, were prepared from the control and cryptorchid rats that were 2-6 weeks of age, and stained with hematoxylin-eosin for morphometry, or stained with antibody against the proliferating cell nuclear antigen (PCNA) to analyze the cell proliferation ability. The thickened cremaster muscle was always associated with cryptorchid testis and, in the case of unilateral cryptorchidism, the cremaster muscle of the contralateral (descended testis) side exhibited normal thickness. The average thickness of the affected cremaster muscle was 0.80 and 1.89 mm at 4 and 6 weeks of age, respectively, although that of the normal muscle was 0.28 and 0.33 mm at the same time period, respectively. Our results showed that the cremaster muscle of the cryptorchid rats was significantly thicker than that of the control rats. The immunohistochemical analysis revealed that a thickened cremaster muscle contained many PCNA-positive nuclei even at 4 weeks of age, in contrast to the control, which had only a few positive nuclei. Our present study indicates that continuous proliferation of the muscle cells associated with cryptorchid testis increases the thickness of cremaster cells in rats exposed to flutamide prenatally. (Reprod Med Biol 2003; : 109-113).
此前，在产前暴露于氟他胺诱导的隐睾大鼠中，我们发现提睾肌增厚。本研究旨在量化隐睾大鼠提睾肌厚度的增加，并研究其与肌细胞增殖的可能关系。为获得隐睾大鼠，在妊娠第16 - 17天，对怀孕的Wistar大鼠皮下注射氟他胺（每天100 mg/kg）。从2 - 6周龄的对照大鼠和隐睾大鼠制备包含睾丸和提睾肌的阴囊连续切片，用苏木精-伊红染色进行形态测量，或用抗增殖细胞核抗原（PCNA）抗体染色以分析细胞增殖能力。增厚的提睾肌总是与隐睾相关，在单侧隐睾的情况下，对侧（下降睾丸）侧的提睾肌厚度正常。受影响的提睾肌在4周龄和6周龄时的平均厚度分别为0.80和1.89 mm，而正常肌肉在同一时期的平均厚度分别为0.28和0.33 mm。我们的结果表明，隐睾大鼠的提睾肌明显比对照大鼠的厚。免疫组织化学分析显示，与对照相比，增厚的提睾肌即使在4周龄时也含有许多PCNA阳性核，而对照只有少数阳性核。我们目前的研究表明，与隐睾相关的肌细胞持续增殖增加了产前暴露于氟他胺的大鼠提睾肌细胞的厚度。（《生殖医学与生物学》2003年；：109 - 113）
