Résumé
Aim To investigate the mechanism of platelet-activating factor(PAF) induced injury on the cultured rat pulmonary microvascular endothelial cells(RPMVEC),and the interfering action of breviscapine. Methods RPMVEC were isolated from Wistar rat and cultured in vitro, the effects of PAF on morphology,monolayer permeability and F-actin of RPMVEC were observed, F-actin expression was evaluated by flow cytometry. Results PAF in the concentration over 0.1 mg?L -1 induced detachment and rupture of RPMVEC within 48 h. 10 mg?L -1 of PAF increased permeability of RPMVEC monolayer and induced depolymerization of F-actin within 120 min.Breviscapine inhibited these effects of PAF. Conclusion ①The detachment and rupture of RPMVEC induced by PAF depends on the exposed concentration and time.②The increased permeability of RPMVEC monolayer induced by PAF is significantly correlated with the depolymerization of F-actin. ③The increased permeability of RPMVEC monolayer and depolymerization of F-actin induced by PAF can be markedly inhibited by breviscapine, which exerts protective action on RPMVEC injury induced by PAF.
Résumé
Blood Replenishing Angelica Decoction [Danggui Buxue Tang (DGBXT)]is a wellknown TCM prescription composed of Radix Angelicae Sinensis and Radix Astragali with the actions ofinvigorating "Qi" and enriching blood. Its action to curtail endothelial permeability induced by histaminewas studied. Endothelial cells isolated from the aorta of neonatal calf were cultured on polycarbonate mi-croporus filter membrane to develop a confluent endothelial monolayer. After purfused with either plainHank's balanced salt solution or that containing 5 g/L albumin, the monolayer was treated with 10-4 mol/L histamine for 30 min either with or without preincubation for 60 min with 10-4 g/mL of DGBXT. Fluidfiltration coefficient (Kf), filtration volume (Jv) and osmotic reflective coefficient (σ) of protein were thenmeasured. The findings showed that DGBXT could curtail the lowering of Kf and Jv and elevation of σ in-duced by histamine, indicating that DGBXT could inhibit the action of histamine on endothelial permeabili-ty, but its mechanism of action needs further study.