Morphological changes in basement membrane associated with jejunal graft injury

Jejunal mucosa injury and morphometric continuity of the intestinal epithelial basement membrane (BM) in experimental groups after 1 h and 6 h of reperfusion following intestinal heterotopic allotransplation in male Wistar rats were observed. Intestinal graft tissue was compared to the jejunum of recipients. Significant damage to the jejunal mucosa was detected and followed by complete intestinal villi destruction, damage to epithelial intestinal crypts and the surrounding lamina propria mucosae. There was a local interruption of BM continuity, as well as its absence in particular areas. The percentage of continuous, clearly visible and undamaged BM detected using the periodic acid and Schiff reagent (PAS) method was 22.4% in the graft samples taken 1 h after transplantation. In the same samples, 43.1% undamaged BM was visualised by silver impregnation. Disappearance of the BM was significant in comparison with recipient samples using both staining methods (both p < 0.001) Biopsies of the intestinal mucosa graft 6 h after transplantation showed significant reduction of the damage to the jejunal mucosa (p < 0.05 and p < 0.01, respectively). The percentage of continuous, clearly visible and undamaged PAS-positive BM was 54%, and argyrophilic BM rose to approximately 83%. The difference between BM continuity detected by PAS method was significant when comparing graft and recipient samples (p < 0.001), but impregnation method did not revealed significant distinction. Based on our results, the silver impregnation method seems to be more sensitive to damage assessment of the jejunal graft.