茶多酚对急性低氧促培养的兔肺小动脉平滑肌细胞产生血栓素A_2和前列环素的影响

目的　观察茶多酚 (teapolyphonels,TP)对肺内小动脉平滑肌细胞 (PASMCs)产生血栓素A2 (TXA2 )和前列环素(PGI2 )及其比值的变化的影响 ,以探讨茶多酚对肺血管的作用及其途径。方法　采用培养的家兔PASMCs为材料 ,用放射免疫法测定在低氧和常氧及环加氧酶抑制剂吲哚美辛干预下 ,培养液中血栓素B2 (TXB2 )和 6 酮 PGF1α的含量。结果　低氧使PASMCs培养液中TXB2 和 6 酮 前列腺素F1α(6 keto PGF1α)含量及其比值显著增加。常氧和低氧条件下 ,终浓度为 3× 10 -5mol·L-1的茶多酚轻微降低TXB2 而明显提高 6 酮 PGF1α的含量 ;终浓度为 2 5× 10 -5mol·L-1的吲哚美辛明显降低TXB2 和 6 酮 PGF1α含量 ;茶多酚和吲哚美辛共同作用 ,TXB2 的含量降低无显著性 ,而 6 酮 PGF1α含量比单纯用吲哚美辛增加明显。结论　茶多酚可能通过增强PASMCs内PGI2 合成酶的活性在低氧时增强PASMCs产生PGI2 ,使TXA2 与PGI2 的比值显著降低而逆转低氧性肺血管收缩。

Effects of TP enhancement of synthesis of TXA_2 and PGI_2 in cultured intra-pulmonary arteriolar smooth muscle cells under acute hypoxia

AIM To study the effect of tee polyphenols(TP) on contennts of thromboxane B 2,6 keto prostaglandin F 2 alpha (TXB 2, 6 Keto PGF 1α ) and their ratio under normoxia and acute hypoxia in the medium of intra pulmonary arteriolar smooth muscle cells (PASMCs). METHODS PASMCs were cultured under normoxia and acute hypoxia, and the contennts of thromboxane B 2,6 keto prostaglandin F 2α (TXB 2, 6 Keto PGF 1α ) were assayed through radioimmunoassay. RESULTS The concentration of thromboxane B 2,6 keto prostag landin F 2α (TXB 2, 6 Keto PGF 1α ) and their ratio significantly increased in the medium of intra pulmonary arteriolar smooth muscle cells (PASMCs) under acute hypoxia. Under either normoxia or hypoxia the concentration of TXB 2 lightly decreased with addition of Tea polyphenols(TP), while that of 6 Keto PGF 1α significantly increased. With the addition of indomethacin,however, under similar condition,the concentrations of both TXB 2 and 6 Keto PGF 1α decreased. Furthermore, the effect of indomathecin on 6 Keto PGF 1α concentrations could be reversed by TP. CONCLUSION Hypoxic pulmonary vascular constriction was reversed through enhance of activity of PGI 2 synthetase by TP.