Possible involvement of eicosanoids in alpha-naphthylthiourea-induced pulmonary oedema and alteration of angiotensin-converting enzyme activity.
alpha-Naphthylthiourea (ANTU) when injected intraperitoneally to rats at a dose of 10 mg/kg elicited lung oedema indicated by an increase in lung weight/body weight (LW/BW) ratio and pleural effusion. The injection of acetylsalicylic acid, which is a cyclo-oxygenase inhibitor, and BW 755C, a cyclo-oxygenase and lipoxygenase inhibitor, prior to ANTU produced a significant inhibition in pleural fluid accumulation without changing the LW/BW ratio. BW A4C, a selective 5-lipoxygenase inhibitor, however, caused a highly significant inhibition in pleural effusion and a slight but significant decrease in LW/BW ratio. Thromboxane A2 synthetase inhibitor, UK 38485, caused a slight but significant inhibition in pleural fluid accumulation without altering the LW/BW ratio. Iloprost, however, produced a slight but significant inhibition in the LW/BW ratio without reducing the pleural effusion rate. A significant decrease in angiotensin-converting enzyme (ACE) activity in the isolated perfused lungs of ANTU-treated rats was noted. This observation was thought to be an evidence of a functional alteration of the lung vascular endothelium. The possible role of eicosanoids in lung oedema induced by ANTU and the related mechanisms of decreased ACE activity are discussed.
Ercan
Z S
ZS
Department of Pharmacology, Medical Faculties, Gazi, Turkey.
Eren
S
S
Zengil
H
H
Türker
R K
RK
D000818:Animals; D015777:Eicosanoids / Q000502:physiology*; D005260:Female; D066298:In Vitro Techniques; D008168:Lung / Q000187:drug effects; D008297:Male; D007703:Peptidyl-Dipeptidase A / Q000187:drug effects / Q000502:physiology*; D010477:Perfusion; D011654:Pulmonary Edema / Q000139:chemically induced* / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D013890:Thiourea / Q000031:analogs & derivatives / Q000494:pharmacology
D015777:Eicosanoids; D007703:Peptidyl-Dipeptidase A; D013890:Thiourea; C005277:alpha-naphthyl thiourea