Tainosho Sachi, Naito Munekazu, Hirai Shuichi, Terayama Hayato, Qu Ning, Itoh Masahiro
Department of Anatomy, Tokyo Medical University, 6-1-1 Shinjuku, Shinjuku-ku, Tokyo, 160-8402, Japan.
Med Mol Morphol. 2011 Mar;44(1):34-8. doi: 10.1007/s00795-010-0501-8.
Previous studies have demonstrated that the blood-testis barrier (BTB) at the tubuli recti (TR) and the rete testis (RT) is less complete than at the seminiferous tubules (ST). However, there has been no report focusing on the basal lamina, which is an important component of the BTB at both TR and RT. In the present study, we performed electron microscopic observation of the basal lamina at the TR and RT, in comparison with that of those of the ST in normal mice. The results showed that the basal lamina of modified Sertoli cells at the TR segment exhibited a wavy and multilayered structure, but the Sertoli cells of ST and the epithelium of RT had an almost flat and single-layered basal lamina. It was also noted that wide gaps existed between the modified Sertoli cells, the basal lamina of the epithelial layer, and the myoid cell layer at the middle TR segment. This characteristic structure of the basal lamina of the TR epithelial layer may be one of the factors for its incomplete BTB.
以往研究表明，直精小管（TR）和睾丸网（RT）处的血睾屏障（BTB）不如生精小管（ST）处的完整。然而，尚无关于基底膜的报道，而基底膜是TR和RT处BTB的重要组成部分。在本研究中，我们对正常小鼠的TR和RT处的基底膜进行了电子显微镜观察，并与ST处的进行了比较。结果显示，TR段修饰的支持细胞的基底膜呈现波浪状和多层结构，但ST的支持细胞和RT的上皮细胞具有几乎平坦的单层基底膜。还注意到，在TR中段，修饰的支持细胞、上皮层的基底膜和肌样细胞层之间存在较宽的间隙。TR上皮层基底膜的这种特征性结构可能是其BTB不完整的因素之一。
