The regulatory effect of endothelial cells of pulmonary arteriole on the tone of pulmonary artery / 中国病理生理杂志

ABSTRACT

The regulatory effect of endothelial cells of the rabbit pulmonary arteriole(PAECs) on the tone of pulmonary artery was studied. The conditioned medium (CM) ofPAECs, cultivated under normal and hypoxic condition for 24 hours, did not induce con-striction of pulmonary artery ring. The aqueous phase was able to induce the constriction.The constriction of pulmonary artery rings was reduced by the heated aqueous phase, but it was disappeared when the heated aqueous phase was treated with trypsin. The constric-tion caused by heated aqueous phase was stronger in hypoxic endothelial cells than innormal cells. Treatment of PAECs with indomethacin and captoril, and administration ofFPL 55712, BN 52021, chlorpheniramine and prazozin to contraction pool did not affectthe constriction of pulmonary artery rings. It was concluded that PAECs might producelong half-life lipid substances which could induce the dilatation of pulmonary artery.Hypoxia inhibted the release of long half-life aqueous heat-unstable vasoconstrictive sub-stances. but enhanced that of the heat-stable fraction which was probably a peptide.