EFFECT OF OBSTRUCTIVE-JAUNDICE ON NEUTROPHIL CHEMOTACTIC ACTIVITY - AN IN-VIVO ASSESSMENT IN ZYMOSAN-INDUCED PERITONITIS MODEL IN RATS

The effect of obstructive jaundice on local neutrophil accumulation in response to inflammatory stimulus was investigated in rats. Obstructi ve jaundice was produced by bile duct ligation for 7 days. Zymosan (20 0 mg) was injected intraperitoneally and 4 h later myeloperoxidase act ivity in the peritoneal fluid was measured to quantify neutrophil recr uitment. Zymosan-induced neutrophil recruitment was significantly grea ter (more than two-fold) in bile duct-ligated rats than in sham-ligate d or normal animals. Depletion of peritoneal cells significantly suppr essed neutrophil recruitment after zymosan injection in all three grou ps, with no significant differences between the groups. In normal rats , replacement of their peritoneal cells by those from bile duct-ligate d rats did not enhance zymosan-induced neutrophil recruitment In contr ast, bile duct-ligated rats treated with peritoneal cell replacement f rom normals showed significantly increased neutrophil recruitment afte r zymosan injection. In vitro neutrophil chemotaxis in response to for myl-Met-Leu-Phe was significantly enhanced in bile duct-ligated rats, compared with that in sham-ligated animals. The results suggest that l ocal neutrophil recruitment in response to inflammation may be enhance d in obstructive jaundice and that increased neutrophil chemotactic ac tivity, not macrophage activity, may play a prime role in the mechanis m.