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.
Department of Pharmacology, Medical Faculties, Gazi, Turkey.
Z S
ZS
Ercan
S
S
Eren
H
H
Zengil
R K
RK
Türker
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