Role of thromboxane A2 and platelet activating factor in early haemodynamic response to lipopolysaccharide in rats
Bocheński, J.; Chłopicki, S.; Gryglewski, R.J.
Journal of Physiology and Pharmacology An Official Journal of the Polish Physiological Society 50(2): 287-297
1999
ISSN/ISBN: 0867-5910 PMID: 10424723 Document Number: 500768
The mechanism of early pulmonary and systemic haemodynamic response to intravenous infusion of LPS from Escherichia coli was investigated in anasthetised Wistar rats. 10 mg of LPS given at a rate of 4 mg/kg/min but not at a rate of 1 mg/kg/min induced an increase in pulmonary arterial pressure (PAP) and a fall in systemic arterial pressure (SAP). Pretreatment with a PAF receptor antagonist; WEB 2170 (5 and 25 mg/kg) inhibited both PAP and SAP responses to LPS (4 mg/kg/min) while an inhibitor of thromboxane synthesis; Camonagrel (10 and 20 mg/kg) abolished PAP response without a major effect on SAP response to LPS. In conclusion, both PAF and TXA2 mediate LPS induced rise in pulmonary arterial pressure while LPS-induced fall in systemic arterial pressure is mediated by PAF.