IMMUNOCYTES AND ABNORMAL GASTROINTESTINAL MOTOR-ACTIVITY DURING ILEITIS IN DOGS

Infiltration of specific immunocytes and stimulation of abnormal gastr ointestinal motor activity during deal inflammation induced by mucosal exposure to ethanol and acetic acid were investigated in 17 dogs. Ile al inflammation significantly increased the frequency of giant migrati ng contractions (GMCs) and decreased the frequency of migrating motor complexes (MMCs). The frequency of retrograde giant contractions (RGCs ) increased only on the day of ethanol and acetic acid treatment. Diar rhea, urgency of defecation, and apparent abdominal discomfort were re lated to the increased frequency of GMCs. Ileal inflammation also prol onged the duration of postprandial MMC disruption. Histological and im munohistochemical findings indicated transmural inflammation with mark ed increase in polymorphonuclear cells in the lamina propria and muscu laris externa layers. Myeloperoxidase activity increased severalfold i n both layers. Cells containing interleukin-2 receptor (IL-BR) increas ed in the lamina propria. Other immunocytes, such as B and T lymphocyt es, dendritic cells, and human leukocyte antigen DR-1 (HLADR)-positive cells, did not exhibit a significant increase in the inflamed ileum c ompared with the normal proximal jejunum. We conclude that stimulation of GMCs may be the major motility marker of intestinal inflammation.