Laboratory of Cell Biology, Ariel University, 40700, Ariel, Israel.
J Mol Histol. 2019 Apr;50(2):141-154. doi: 10.1007/s10735-019-09813-3. Epub 2019 Jan 18.
The sperm produced in the seminiferous tubules pass through the rete testis, efferent ducts, and epididymis. The epididymis has three distinct regions known as caput, corpus, and cauda. The transit through the epididymis is an essential process in sperm maturation. The lumen of each epididymal region has a unique fluid composition regulated by many ion channels and transporters in the epithelial cells. The objective of this study was to map the sites of localization of ion channels ENaC and CFTR along the length of the mouse and rat epididymis using confocal microscopic imaging. The integrity of the fine structure of the tissues was verified by fluorescent phalloidin staining of actin filaments visualized by high-resolution confocal microscopy. The 2D and 3D images showed preservation of the stereocilia. Based on these images we determined morphometric parameters of the epithelial cells and ducts. ENaC and CFTR immunofluorescence appeared almost continuously on the apical membrane of caput and in smooth muscle myoid cells. In cauda, CFTR expression was observed continuously in long stretches of epithelium interrupted by clusters of cells that showed no CFTR expression. Similar patterns of localization were observed in both mouse and rat samples. Mutations in the CFTR gene are known to result in male infertility. Based on the widespread presence of ENaC along the epididymis we suggest that mutations in ENaC subunits may also be associated with male infertility. The diverse phenotypes associated with CFTR mutations may be due to malfunction of CFTR at specific subcellular locations in the male reproductive system.
生精小管中产生的精子通过睾丸网、输出小管和附睾。附睾有三个不同的区域，分别称为头部、体部和尾部。精子通过附睾的过程是精子成熟的一个重要过程。每个附睾区域的管腔具有独特的液体组成，由上皮细胞中的许多离子通道和转运体调节。本研究的目的是使用共聚焦显微镜成像技术，绘制离子通道 ENaC 和 CFTR 在小鼠和大鼠附睾中的定位。通过高分辨率共聚焦显微镜观察荧光鬼笔环肽染色的肌动蛋白丝来验证组织精细结构的完整性。二维和三维图像显示了静纤毛的保留。基于这些图像，我们确定了上皮细胞和导管的形态参数。ENaC 和 CFTR 免疫荧光在头部的顶膜和平滑肌肌样细胞上几乎连续出现。在尾部，CFTR 表达在连续的上皮细胞中观察到，上皮细胞中存在由无 CFTR 表达的细胞簇中断。在小鼠和大鼠样本中观察到类似的定位模式。CFTR 基因的突变已知会导致男性不育。基于 ENaC 在附睾中的广泛存在，我们推测 ENaC 亚基的突变也可能与男性不育有关。CFTR 突变相关的不同表型可能是由于 CFTR 在男性生殖系统的特定亚细胞位置功能障碍所致。
