Role of thromboxane A2 and platelet activating factor in early haemodynamic response to lipopolysaccharide in rats.
The mechanism of early pulmonary and systemic haemodynamic response to intravenous infusion of LPS from Escherichia coli was investigated in anesthetised 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.
Bocheński
J
J
Department of Pharmacology, Jagiellonian University Medical College, Krakow, Poland.
Chłopicki
S
S
Gryglewski
R J
RJ
D000818:Animals; D001381:Azepines / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004926:Escherichia coli; D007189:Indans / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008297:Male; D010972:Platelet Activating Factor / Q000037:antagonists & inhibitors / Q000502:physiology*; D010975:Platelet Aggregation Inhibitors / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013928:Thromboxane A2 / Q000502:physiology*; D014230:Triazoles / Q000494:pharmacology
D001381:Azepines; D004791:Enzyme Inhibitors; D007189:Indans; D008070:Lipopolysaccharides; D010972:Platelet Activating Factor; D010975:Platelet Aggregation Inhibitors; D014230:Triazoles; D013928:Thromboxane A2; C063964:bepafant; C103583:camonagrel