Direct effects of platelet-activating factor on pulmonary artery endothelial cells / 中国病理生理杂志

ABSTRACT

Platelet-activating factor(PAF) at different concentrations were added to in vitro cultured bovine=pulmonary artery endothelial cells(BPAEC) when lactate dehydrogenase(LDH) release rate, angiotensin converting enzyme(ACE) activity and malondialdehyde (MDA) content were determined. The influences of specific PAF receptor antagonist on PAF effects and the stimulating effect of PAF on leukocyte-endothelial cell adhesion were also observed. The results showed that when PAF were added to BPAECs, there were no significant change in LDH release rate, ACE activities were only slightly increased. No obvious changes in cellbound MDA, but supernatant MDA content was increased in cells treated with high concentration of PAF (10~(-6)). The PAF receptor antagonist, SRI 63-441 made the cell-bound MDA content higher than that of PAF treated cells, whereas the supernatant MDA became lower. PAF may promote endothelial-leukocyte adhesion either through its effects on endothelial cells or on leukocytes, suggesting that PAF has no obvious damaging effect on endothelial cells but may activate endothelial cells thus promoting endothelialleukocyte adhesion.