IS NITRIC-OXIDE AND HEPARIN TREATMENT JUSTIFIED IN INFLAMMATORY BOWEL-DISEASE - AN EXPERIMENTAL-STUDY

Microcirculatory disturbances of the colon may contribute to the patho genesis of inflammatory bowel disease. The aim of the study was to inv estigate the alterations of rectal blood perfusion in experimental col itis with reference to nitric oxide and heparin treatment. The study w as carried out on 36 rats, divided into six groups: group I, control; group II, control + NG-nitro-L-arginine (L-NNA); group III, colitis wi thout treatment; group IV, colitis + L-arginine; group V, colitis + L- NNA; group VI, colitis + heparin treatment. Experimental colitis was i nduced by 4% acetic acid enema, and 48 h after the enema, besides the measurement of rectal capillary blood flow by means of laser Doppler f lowmetry, the serum interleukin-6 (IL-6) level and histopathological a lterations within the rectal mucosa were examined. Experimental coliti s resulted in a drop in rectal wall perfusion. L-Arginine and heparin treatment improved the microcirculatory values. The highest IL-6 level and the most advanced histopathological alterations were observed in the rats treated with L-NNA. L-Arginine treatment had no influence on IL-6 concentration, however it aggravated the inflammatory changes wit hin the rectal mucosa. Heparin administration reduced the IL-6 values and also had a positive impact on the microscopic alterations within t he rectal wall. It is concluded that heparin treatment has a beneficia l effect on the microcirculatory disturbances and inflammatory changes observed in experimental colitis. The inhibition of nitric oxide-synt hase aggravated the course of experimental colitis. L-Arginine adminis tration improves the rectal blood flow but aggravates the histopatholo gical alterations within the rectal wall.