Compared to controls, CIE dogs showed what in ileum ASBT protein immunolabeling?

• A. Significantly decreased
• B. No difference
• C. Increased
• D. Significantly increased

Answer: (A)

Inflammation in the ileum tends to dampen the machinery that normally reabsorbs bile acids. ASBT, the apical sodium bile acid transporter, is key for actively reclaiming bile acids from the intestinal lumen. In dogs with chronic inflammatory enteropathy, the inflammatory environment and mucosal damage downregulate enterocyte transporters, including ASBT. This shows up as reduced ASBT protein labeling on immunohistochemistry, i.e., a significantly decreased signal compared with healthy controls. The functional consequence is less bile acid reabsorption in the ileum, which can contribute to alterations in the bile acid pool and may exacerbate diarrhea. So, the finding of a significantly decreased ileal ASBT immunolabeling aligns with the expected impact of ileal inflammation on transporter expression.