Actinomycin D peritonitis in the rat.
Following intraperitoneal injection of actinomycin D rats show a decrease in number of cells present in the peritoneal cavity, reaching the lowest point after 24 hr. At the same time a highly significant increase of free beta-glucoronidase and of the intracellular concentrations of both cyclic AMP and cyclic GMP has been observed. No exudate was present at this time. Measurable quantities of exudate were present 48-72 hr after actinomycin injection concomitantly with an intense cellular immigration, the dominant cell being mononuclears. In this second phase of the reaction the free beta-glucuronidase decreases towards normal values and both the cyclic nucleotides are significantly below the control values. It is suggested that the increase of intracellular cAMP--concomitant with the maximum release of lysosomal enzymes--is a feedback mechanism preventing further release of inflammatory mediators.
D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism; D006152:Cyclic GMP / Q000378:metabolism; D003609:Dactinomycin; D004195:Disease Models, Animal; D005966:Glucuronidase / Q000378:metabolism; D010529:Peritoneal Cavity / Q000378:metabolism; D010538:Peritonitis / Q000139:chemically induced / Q000378:metabolism*; D011458:Prostaglandins E / Q000378:metabolism; D051381:Rats
D011458:Prostaglandins E; D003609:Dactinomycin; D000242:Cyclic AMP; D005966:Glucuronidase; D006152:Cyclic GMP