Lack of release of prostaglandins from isolated perfused lungs during pulmonary hypertension and oedema.

1 The effects on pulmonary prostaglandin synthesis of pulmonary hypertension and oedema have been studied. 2 Seventeen isolated lungs of rabbit, cat and guinea-pig were perfused with plasma, whole blood or Krebs Ringer solution in a recirculating system. 3 The venous effluent from the lungs superfused (10 ml/min) a series of smooth muscle tissues sensitive to prostaglandins and thromboxane A2; these were: rat stomach strip, rat colon, chick rectum and rabbit aorta. 4 Left atrial pressure was increased by between 10 and 30 mmHg for periods of 3 to 59 minutes. Gross alveolar oedema eventually developed in all experiments. 5 Neither pulmonary hypertension nor subsequent oedema caused release of prostaglandins into the venous effluent.