The effect of ventilatory patterns on prostacyclin (PGI2) synthesis in the lung.

Prostacyclin (PGI2) appears to be synthesized in the lungs of man and experimental animals. It has been stated that PGI2 must be regarded as a local hormone that inhibits platelet adhesion to vessel walls only very close to the site of synthesis. The wide range of normal values given for PGI2 may be related to the sensitivity and exclusiveness of the different assay techniques used. In animals hyperventilation increases PGI2 synthesis by the lung, but in agreement with other authors we demonstrated that hyperventilation did not influence PGI2 synthesis in man. We used a radio-immunoassay technique to estimate PGI2 levels.