Release of prostaglandin-like substances during elevations of left atrial pressure in the cat.

The purpose of the present work was to measure prostaglandin (PG)-like activity in arterial blood during acute pulmonary hypertension. Anesthetized cats with the chest opened and given positive pressure ventilation were used. A balloon in the left atrium was inflated to elevate hydrostatic vascular pressure in the lungs.

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.