滨蒿内酯对ryanodine介导哮喘豚鼠气道平滑肌细胞内钙释放的抑制作用

目的该实验就滨蒿内酯(Scoparone,Sco)降低气道平滑肌细胞(airway smooth muscle Cells,ASMC)细胞内钙浓度(cytoplasmic Ca2+concentration,Ca2+]i)的途径及平喘作用的机理进行初步的探讨。方法建立卵蛋白诱导的哮喘豚鼠模型,通过离体豚鼠气管环的舒缩实验和测定培养的ASMCsCa2+]i浓度的方法,分析Sco对哮喘豚鼠ryanodine受体介导的内钙释放的影响。结果显示在细胞外含钙或无钙时,预先给予Scoparone可抑制5μmol/L ryanodine引起的正常、哮喘组豚鼠离体气管环收缩反应;Scoparone可明显降低对照组及哮喘组豚鼠原代培养ASMCsCa2+]i水平且哮喘组更为明显(P<0.01);Scoparone明显降低原代培养的ASMCsCa2+]i对5μmol/L ryanodine的反应性(P<0.01)。结论 Sco明显降低正常和哮喘豚鼠原代培养的ASMCsCa2+]i,对后者的作用明显大于前者;Sco对ASMCs的Ca2+]i降低作用主要是通过抑制细胞内钙释放途径实现的,明显抑制哮喘豚鼠ASMCs ryanodine受体介导的内钙释放。

Inhibition of Ryanodine-induced calcium release by coparone in airway smooth muscle cells from asthmatic guinea-pig

【Objective】 Scoparone(Sco),a coumarin derivative extracted from Artemisia Scoparoneparia Waldst.Et Kit,possesses anti-inflammatory and calcium antagonistic effects,and we found it could significantly relax airway smooth muscle cells(ASMCs) and decrease cytoplasmic Ca2+ concentration(i) of ASMCs in our previous research.In this study,the possible mechanism of the calcium antagonistic effects of Sco was investigated.【Methods】 Using Fluo-3/ AM staining and a fluorescence spectrophotometer system,the intracellular calcium releases activity of cultured ASMCs from normal or ovalbumin-induced asthma guinea pig were measured with or without Sco.【Results】 The results showed that ASM strip and cultured ASMCs from asthma guinea pig maintained the hyperreactivity to 5 μmol/L ryanodine,and Sco dose-relatively decreased i of cultured ASMCs in both control and asthmatic group,and the change of i in asthmatic group was higher than control group(P <0.01),and Sco also significantly inhibited 5 μmol/L ryanodine induced Ca2+ release in cultured ASMCs(P <0.01).【Conclusions】 Therefore,pretreatment of Sco could down regulate ryanodine-induced Ca2+ release activity in cultured ASMCs from asthmatic guinea pigs.