Long-term lung preservation with the PAF antagonist BN 52021

Platelet activating factor (PAF, l-alkyl-2(R)-acetyl- glycero-3-phosphorylcholine) is a phospholipid that is released by a variety of cells. The similarity between the pathophysiological effects of PAF and posttrans-plant pulmonary dysfunction led to an evaluation of a PAF antagonist as an adjunct to lung preservation. The ginkgolide B, BN 52021, was selected as the PAF antagonist to be studied because of the large data base available on this compound. BN 52021 was given to the donor and recipient (10 mg/kg i.v.) prior to harvest and transplantation and was included in 1 L of preservation solution (10 mg/kg) used for flushing the pulmonary artery and for storage. Left single-lung transplantation was performed following a 22-hr preservation period at 10°C. Arterial oxygen tension (pO₂), pulmonary vascular resistance (PVR), alveolar arterial oxygen difference (A-aDO₂), and dynamic lung compliance (DLC) were recorded for 6 hours following ligation of the native pulmonary artery. At the end of 6 hr pO₂ was 243.5±61.5 vs. 71.7±10.2 mmHg (P<0.02) for the controls. A-aDO₂ was less in the BN 52021 groups: 431.8±58.3 vs. 606.0±9.8 mmHg in the control groups (P<0.001), and PVR was significantly less in the BN 52021 group: 346±70.8 vs. 663±64.3 dynes/sec/cm-⁵ (P<0.035). We conclude that PAF antagonists like BN 52021 may be useful adjuncts for lung preservation. The effects of BN 52021 are easily explained by PAF antagonist activity in ischemic and reperfusion-induced pulmonary dysfunction. However this study does not exclude that BN 52021 may have direct effects.