Jung F, Franke R P
GKSS Research Centre Geesthacht, Berlin-Brandenburg Center for Regenerative Therapies (BCRT), Campus Virchow-Klinikum der Charité, Universitätsmedizin Berlin, Germany.
Microvasc Res. 2009 Sep;78(2):241-5. doi: 10.1016/j.mvr.2009.02.010. Epub 2009 Mar 10.
While structure and function of precapillary sphincter cells were assured in skin capillaries it is unclear whether segmental reduction of capillary lumina can occur in human capillaries. It has been shown that endothelial cells are able to exert dynamical reactions. Since the first description of the vascular endothelium a great variety of findings were described concerning the active role of capillary endothelial cells in regulation of the capillary lumen applying intravital microscopy. The intravital microscopy was performed in the framework of an observational study to document the long-term stability of capillaries in healthy subjects over many years. In the second year one of the participants showed remarkable changes in capillaries compared to recent recordings. Control recordings were performed 1, 3, 4, 5 and 20 h after the initial examination - until a complete normalization of the capillaries occurred. This case report is documenting for the first time clearly that extreme luminal narrowing of long segments of cutaneous capillaries can also appear in humans, in this case restricted exclusively to the venular leg of the capillaries. Different from the reductions of the capillary lumen induced by electrical irritation in frogs which lasted only for seconds, the capillary lumen narrowing in this case lasted considerably longer, almost over a whole day. It is important to note that the demonstrated findings did not occur in all capillaries and it remains unclear whether such findings are restricted to skin capillaries or might occur also in other regions of the body or even systemically. It could be demonstrated clearly, however, that segmental narrowing of capillary lumina can occur in humans possibly leading to a temporary stillstand of perfusion.
虽然皮肤毛细血管前括约肌细胞的结构和功能已得到证实，但尚不清楚人类毛细血管是否会出现管腔节段性缩小。研究表明，内皮细胞能够产生动态反应。自首次描述血管内皮以来，应用活体显微镜观察，已描述了大量关于毛细血管内皮细胞在调节毛细血管管腔方面的积极作用的研究结果。活体显微镜观察是在一项观察性研究的框架内进行的，目的是记录多年来健康受试者毛细血管的长期稳定性。在第二年，一名参与者的毛细血管与最近的记录相比出现了显著变化。在初次检查后的1、3、4、5和20小时进行对照记录，直到毛细血管完全恢复正常。本病例报告首次清楚地证明，人类皮肤毛细血管的长节段也会出现极端的管腔狭窄，在本病例中仅局限于毛细血管的静脉段。与青蛙电刺激引起的仅持续数秒的毛细血管管腔缩小不同，本病例中的毛细血管管腔狭窄持续时间长得多，几乎持续了一整天。需要注意的是，所展示的这些发现并非在所有毛细血管中都出现，目前尚不清楚这些发现是否仅限于皮肤毛细血管，还是也可能发生在身体的其他部位甚至全身。然而，可以清楚地证明，人类毛细血管会出现管腔节段性狭窄，这可能导致灌注暂时停止。
