FIG. 5.

Prevention of toxin A-induced mucosal disruption and apoptosis by glutamine (100 mM) or alanyl-glutamine (100 mM) compared to the PBS-treated controls. The left column depicts ileal sections stained with hematoxylin-eosin, and the right column shows the same ileal sections stained by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling method; the brown dots represent apoptotic cells (scale, 1 cm = 70 μm). Severe mucosal disruption (C) and significant amounts of apoptosis in the mucosal cells (D) are seen in the ligated rabbit ileal loops treated with toxin A (10 μg/ml) for 5 h in comparison with controls treated with PBS (A and B). Glutamine (E and F) or alanyl-glutamine (G and H) significantly reduced mucosal disruption and apoptosis induced by toxin A.