Pelletier R M
Department of Anatomy and Neurobiology, Faculty of Medicine, University of Ottawa, Ontario, Canada.
Microsc Res Tech. 1994 Mar 1;27(4):333-49. doi: 10.1002/jemt.1070270408.
The purpose of the present study was to determine whether the blood barrier of the epididymis and vas deferens acted synchronously or not with the blood barrier of the testis. The permeability of the blood-epididymis and blood-vas deferens barrier was tested in neonatal kit mink up to puberty and monthly in adult minks throughout the annual seasonal reproductive cycle. Attention was focused particularly on time intervals when the blood barrier of the testis has been documented to be permeable, namely, before puberty and during testicular regression in the adult. One of two electron-opaque permeability tracers was perfused into the blood stream: horseradish peroxidase (HRP) or lanthanum nitrate. The convoluted tube of the epididymis was divided into three anatomical regions: the caput, corpus, and cauda. The vas deferens was divided into proximal and distal regions. At birth and throughout puberty, the three regions of the epididymis and the two of the vas deferens showed a lumen and a competent blood barrier. In the adult, a lumen persisted in the epididymis and vas deferens throughout the annual seasonal reproductive cycle, and the blood barrier of the excurrent duct remained impermeable even when the blood barrier in the testis became momentarily permeable during testicular regression. When HRP was used to test the permeability of the blood-tissue barrier of the excurrent ducts, no tracer deposits were observed on the lumenal surface of the epithelium. Conversely, when lanthanum served as the tracer, deposits of the probe were associated with microvilli and intracellular membranes despite impermeability of tight junctions. The data show that the lanthanum technique can yield false-positive results. The findings also indicate that 1) a blood-excurrent duct barrier is established before the blood-testis barrier and 2) the two barriers act asynchronously. It is therefore plausible that they are modulated by distinct factors.
本研究的目的是确定附睾和输精管的血屏障与睾丸的血屏障是否同步发挥作用。在新生水貂直至青春期期间，以及成年水貂全年季节性生殖周期中每月对血附睾屏障和血输精管屏障的通透性进行测试。特别关注睾丸血屏障被证明具有通透性的时间间隔，即在青春期前和成年期睾丸退化期间。将两种电子不透明的通透性示踪剂之一注入血流：辣根过氧化物酶（HRP）或硝酸镧。附睾的蟠曲小管分为三个解剖区域：头部、体部和尾部。输精管分为近端和远端区域。在出生时及整个青春期，附睾的三个区域和输精管的两个区域均显示有管腔和有效的血屏障。在成年期，附睾和输精管在全年季节性生殖周期中均保持有管腔，即使在睾丸退化期间睾丸的血屏障暂时变得通透时，输出管道的血屏障仍保持不通透。当使用HRP测试输出管道的血组织屏障的通透性时，未在上皮细胞的管腔表面观察到示踪剂沉积。相反，当使用镧作为示踪剂时，尽管紧密连接不通透，但探针的沉积与微绒毛和细胞内膜相关。数据表明镧技术可能产生假阳性结果。研究结果还表明：1）血输出管道屏障在血睾屏障之前建立；2）这两种屏障异步发挥作用。因此，它们受不同因素调节似乎是合理的。
