Tumor necrosis factor unresponsiveness after surgery in bile duct ligated rats. Houdijk, A. P. J., M. A. Boermeester, R. I. C. Wesdorp, C. Erik Hack, and P. A. M. Van Leeuwen. Departments of Surgery and Internal Medicine, Free University Hospital: Central Laboratory of the Netherlands Red Cross Blood Transfusion Service and Laboratory for Experimental and Clinical Immunology, University of Amsterdam, Amsterdam, the Netherlands
APStracts 3:0116G, 1996.
In obstructive jaundice postoperative complications are related to gut derived endotoxemia and possibly mediated by cytokines like TNF and IL-6. This study investigated the course of IL-6 and TNF following surgery in bile duct ligated rats (BDL) treated with and without an enteral endotoxin binder (cholestyramine). Endotoxin in rat plasma was determined by blocking cytokine production in whole blood cell cultures stimulated by rat plasma using antibodies directed against the endotoxin (CD14) receptor. Results showed that in saline treated BDL rats (BDL-SAL) surgery elicited a significant IL-6 response. TNF however remained at its low preoperative levels. Cholestyramine treatment resulted in undetectable preoperative TNF and IL-6 levels but both cytokines were significantly raised after surgery. Endotoxin, as determined by the CD14 blockade test, was identified in the BDL-SAL group before (t=0 hrs) and after surgery (t=2 and 4 hrs) whereas in the cholestyramine group endotoxin was only present at t=2 hrs following surgery. The lack of a postoperative plasma TNF response in the BDL-SAL group, in the continuous presence of endotoxin, suggests endotoxin tolerance for TNF production in obstructive jaundice.

Received 10 January 1996; accepted in final form 28 May 1996.
APS Manuscript Number G12-6.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 28 June 96