Scelsi R, Scelsi L, Gritti A, Gozo M, Reguzzoni M, Marchetti C
Department of Human Pathology, University of Pavia, Italy.
Lymphology. 1996 Jun;29(2):60-6.
The localization, morphology and fine structure of initial lymphatic vessels in the mucosa of the empty and distended urinary bladder were studied. Endoscopic transurethral biopsies of the empty (collapsed) bladder showed under light and electron microscopy numerous intramural lymphatics with a dilated lumen and thin profile. Contacts between endothelial cells were single, overlapping, interlocking, and open while the perivascular connective tissue was filled by fascicles of collagen fibers. In the most superficial layer (subepithelial mucosa), lymphatics were not seen. Biopsies obtained under elevated intraluminal pressure and distension showed on light and electron microscopy lymphatic vessels with small lumens characteristically reduced to irregular slits. Endothelial cell contacts were simple or overlapping; open junctions were rare. The perivascular connective tissue was dense and collagen and elastic fibers often abutted one another. These findings support that with a distended or expanded urinary bladder, the effect of increased intraluminal pressure on the superficial (mucosal) layer radially pulls on the connective tissue that in turn compresses the initial lymphatics thereby restricting lymph transport.
对空虚和充盈状态下膀胱黏膜中初始淋巴管的定位、形态及精细结构进行了研究。经尿道对空虚（塌陷）膀胱进行内镜活检，在光镜和电镜下可见大量壁内淋巴管，管腔扩张，轮廓纤细。内皮细胞之间的连接呈单排、重叠、互锁及开放状，而血管周围结缔组织充满胶原纤维束。在最表层（上皮下黏膜）未见淋巴管。腔内压力升高及膀胱充盈时获取的活检标本，在光镜和电镜下可见管腔小的淋巴管，其特征性地缩小为不规则缝隙。内皮细胞连接为简单或重叠状；开放连接少见。血管周围结缔组织致密，胶原纤维和弹性纤维常相互邻接。这些发现支持，在膀胱充盈或扩张时，腔内压力升高对表层（黏膜）的作用会径向牵拉结缔组织，进而压迫初始淋巴管，从而限制淋巴运输。
