Non-hypoxaemic pulmonary oedema induced by alpha-naphthyl thiourea in the rat.
The time course of the respiratory consequences of alpha-naphthyl thiourea (ANTU)-induced lung oedema was studied in adult albino rats, up to 6 h after the injection of 5 mg/kg ANTU. Control rats were injected with olive oil (ANTU solvent). After 6 h, pulmonary extravascular water increased by 50% in ANTU-treated rats and the volume of the pleural effusion reached 3.4 +/- 0.1 ml (mean +/- s.e. mean). The most striking point is the absence of hypoxaemia in the ANTU-treated rats: PaO2 = 103 +/- 1.5 Torr vs 100 +/- 1 Torr in the control rats. The non-decreased PaO2 can be related to the patency of the alveolar airspaces. The predominant location of the oedema in the lung interstitium is caused by a specific lymphatic drainage pathway towards the pleura in the rat which prevents alveolar flooding. Histological findings support this hypothesis. PaCO2 is unaltered: 32 +/- 1 Torr in ANTU rats vs 33.5 +/- 1 Torr in control rats. A slight downward shift of arterial pH is found in ANTU rats: (7.440 +/- 0.010 vs 7.475 +/- 0.010, P less than 0.01). Concomittently (HCO3-)a decreases in ANTU-treated rats (22.2 +/- 1.2 mmol l-1 vs 24.8 +/- 0.6 mmol l-1, P less than 0.01). The absence of hypoxaemia is common with normobaric oxygen (02) and ANTU-induced lung oedema in the rat. A comparison is made between 02 and ANTU toxicity, as for respiratory events and histological features.
D000818:Animals; D001794:Blood Pressure; D001831:Body Temperature; D002245:Carbon Dioxide / Q000097:blood; D006339:Heart Rate; D006400:Hematocrit; D006863:Hydrogen-Ion Concentration; D007773:Lactates / Q000097:blood; D008168:Lung / Q000648:ultrastructure; D008297:Male; D010100:Oxygen / Q000097:blood; D011654:Pulmonary Edema / Q000097:blood / Q000139:chemically induced* / Q000473:pathology; D051381:Rats; D011919:Rats, Inbred Strains; D013890:Thiourea / Q000031:analogs & derivatives* / Q000633:toxicity
D007773:Lactates; D002245:Carbon Dioxide; D013890:Thiourea; D010100:Oxygen; C005277:alpha-naphthyl thiourea