Helicobacter pylori lipopolysaccharide provokes iNOS-mediated acute systemic microvascular inflammatory responses in rat cardiac, hepatic, renal and pulmonary tissues

We have examined the effects of intravenous administration of a purified li popolysaccharide (LPS) from Helicobacter pylori (3 mg kg(-1), i.v.) on rat vascular permeability, assessed by the radiolabelled human serum albumin le akage technique in the heart, kidney, liver and lung 4 h after challenge. A n increased vascular permeability in cardiac, renal, hepatic and pulmonary tissues after challenge was determined. The albumin leakage observed in all these organs could be prevented by the selective inducible nitric oxide sy nthase inhibitor, N-(8-(aminomethyl)benzyl)-acetamidine (1400W; 0.2-1 mg kg (-1), s.c.) administered concurrently with LPS. Thus, H. pylori LPS can pro voke a microvascular inflammatory response in the rat cardiac, renal, hepat ic and pulmonary tissues, actions mediated through the activation of the in ducible nitric oxide synhase isoenzyme. (C) 2001 Elsevier Science Ltd. All rights reserved.