[GFAP immunoreactivity in newly formed ileal mucosa in a serosal patch in dog colon]

A Short bowel was induced in 8 beagle bitches by resecting 85% of the small intestine. Following resection, a tangential fixation was performed in antiperistaltic direction between the ileum and the proximal colon. A 15 cm segment of the remaining ileum was incised opposite to its mesenterial attachment and sewn onto the serosa of the neighboring segment of colon (Serosa patching). After 20 weeks of observation, segments of the ileum, the colon and the anastomosed intestinal segment were removed. The neomucosa covering the patch surface was investigated using immunohistochemical methods in order to demonstrate the presence of nerve fibers. The immunofluorescence reaction using anti-GFAP (glial fibrillary acidic protein) clearly demonstrated immunoreactivity in the formed neomucosa and in the underlying granulation tissue. The immunoreactive fibers were comparable with fibers demonstrated in the original mucosa. This finding is an indication that the neomucosa of a serosa patch may be functionally intact because the presence of nerves suggests that mucosal functions, e.g. resorption and secretion, are under nervous regulation.