SYNERGISTIC EFFECTS OF TUMOR-NECROSIS-FACTOR AND MORPHINE ON GUT BARRIER FUNCTION

Objective: To study the effects of tumour necrosis factor (TNF) and mo rphine on intestinal permeability, intestinal transit and bacterial tr anslocation in the rat. Design: A randomized interventional controlled experiment. Setting: University surgery and microbiology research lab oratory. Participants: Forty-four rats in five groups as follows: cont rol (n = 9); treated with morphine every 2 hours for 8 hours (n = 9); treated with TNF for 5 minutes (n = 10); treated with TNF plus morphin e every 2 hours for 8 hours (n = 6); and treated with TNF plus morphin e every 3 hours for 24 hours (n = 10). Main Outcome Measures: Intestin al permeability as measured by the uptake of chromium-51 ethylenediami netetraacetate Cr-51-EDTA) over 8 hours, intestinal transit as measure d by the amount of Cr-51-EDTA remaining the gastrointestinal tract at the time of animal sacrifice, intestinal bacteria counts and transloca tion of bacteria as measured from bacterial counts of mesenteric lymph nodes, spleen and liver at the time of sacrifice. Results: Morphine i ncreased intestinal transit time and ileal bacteria counts (p < 0.05). TNF alone did not increase intestinal permeability or bacterialf tran slocation. TNF plus morphine increased intestinal transit time, intest inal permeability, bacterial counts and bacterial translocation (p < 0 .05). Conclusions: Morphine or increased intestinal transit time, or b oth, increases the concentration of intestinal bacteria. Morphine plus TNF increases intestinal bacteria counts, intestinal permeability and bacterial translocation. Morphine alone does not increase intestinal permeability or bacterial translocation.