Changes of colonic mucosal microcirculation and histology in two colitis models: an experimental study using intravital microscopy and a new histological scoring system.

This study investigated capillary blood flow (CBF) and pathomorphological alterations in the mucosa of different bowel segments at different times after disease onset in rats with colitis induced by either trinitrobenzensulfonic acid (TNBS) or mitomycin-C. CBF was determined by intravital microscopy using fluorescein-labeled erythrocytes. The histological degree of inflammation was assessed by a new scoring system. Severe acute histological changes were found in the distal colon 24 hr after induction of TNBS colitis (score: 8.9+/-1.0). CBF was increased (2.9+/-0.05 vs. 2.6+/-0.04 nl/min in healthy controls). The histological alterations persisted until day 3 (8.5+/-0.9) when CBF significantly decreased (1.8+/-0.05 nl/min). After 15 days, moderate acute inflammation was still detectable histologically (5.4+/-1.3), but CBF had returned to normal values. In mitomycin-C colitis, changes developed mainly in the proximal colon: After three days, there was mild inflammation (2.8+/-1.2) with normal CBF (2.5+/-0.1 nl/min). After seven days, the inflammation had increased (4.8+/-1.1), while CBF had decreased (1.5+/-0.06 nl/min). These changes persisted for six weeks (5.3+/-0.7; 1.2+/-0.05 nl/min). These data suggest that disturbed colonic microcirculation may play an important role in the pathogenesis of inflammatory bowel disease regardless of the histopathomorphological alterations.

Testicular microlithiasis and concomitant testicular intraepithelial neoplasia.

We report a case of testicular microlithiasis developing during cancer follow-up in a previously normal testicle. Biopsy revealed testicular intraepithelial neoplasia which was treated with radiotherapy. We believe that especially in cancer follow-up newly developing microlithiasis must lead to biopsy to rule out otherwise undetectable germ cell neoplasia precursor.

[Protective effect of glutamine on microcirculation of the intestine in experimental colitis]. / Protektiver Effekt von Glutamin auf die Mikrozirkulation des Darms bei experimenteller Colitis.

Parenteral glutamine application can stabilize intestinal permeability and mucosal integrity. It is not known whether glutamine influences the microcirculation in the large intestine. This study thus employs intravital microscopy to investigate mucosal microcirculation in the ascending and descending Colon of Sprague-Dawley rats with TNBS colitis. The animals were randomized and treated with either saline solution (placebo) or glutamine (verum). In the severely inflamed descending colon, TNBS colitis involves a significant capillary blood flow reduction that is not improved by glutamine application. Though the ascending colon shows only a mild inflammatory reaction, its microcirculation is likewise significantly reduced. Here glutamine therapy is associated with an increase in capillary blood flow, indicating that it has a protective effect on the microcirculation of the secondarily involved intestinal segment.