火把花根片对哮喘大鼠气管平滑肌细胞L型钙通道的作用

目的　探讨火把花根片对哮喘大鼠气管平滑肌细胞L型钙通道 [L typecalcium (L LCa)channel]的作用。方法　将♂Wistar大鼠分为正常对照组、哮喘组、火把花根片(Huobahuagentablet,HBT)治疗组及地塞米松 (dexametha sone,DXM )治疗组共 4组 ,分别给予相应的处理 ,观测大鼠支气管平滑肌细胞L LCa在正常时 ,哮喘发作时 ,以及给予HBT及DXM治疗后的变化。结果　火把花根片治疗后的哮喘大鼠的L LCa与哮喘组以及正常对照组大鼠通道开放概率相比差异均有显著性 (P <0 0 5 )。哮喘组通道L LCa开放时间常数 (τO1和τO2 )延长 ,关闭时间常数 (τc1和τc2 )缩短 ,与正常对照组相比差异有显著性 (P <0 0 5 )。火把花根片与地塞米松治疗后的哮喘大鼠的L LCa与哮喘组相比通道开放时间常数缩短 ,关闭时间常数延长。结论　哮喘大鼠L LCa的活动明显增强。经火把花根片治疗后L LCa活动有所减弱 ,表现为通道开放时间常数缩短 ,关闭时间常数延长。提示火把花根片与地塞米松均可明显抑制哮喘大鼠的L LCa的活动 ;HBT与DXM均可逆转哮喘大鼠L LCa动力学的改变。

Effect of huabahuagen tablet on L-type calcium channel of trachea smooth muscle cells in rats with asthma

Aim To study the effects of huabahuagen tablet on voltage sensitivity of calcium channels in trachea smooth muscle cell (TSMC) of asthma rats. Methods Male wistar rats were randomly divided into four groups: group A (n=10) were control and untreated; Group B (n=9) were asthma control group; group C (n=10) were treated with huobahuagen tablets, and group D (n=10)were treated with DXM. Single TSMC was acutely isolated from the rats. Single channel currents were recorded by using the patch clamp technique in on-cell attach configuration. Results ① Compared with group A, the L-L Ca channel activity increased significantly in group B on the on-cell attach recording. Channel open probability(Po) of L-L Ca channel in group B increased significantly compared with that in group A (P<0.05 ). Channel open time constants(τ O1 andτ O2) prolonged significantly in group B; Close time constants (τ c1 and τ c2)shortened significantly. ② While in group C, which was treated with huobahuagen tablets, Channel open time constants(τ O1 andτ O2) and Close time constants (τ c1 and τ c2) kept unchanged (P>0.05). At the same time compared with group B,the L-L Ca Channel open time constants(τ O1 andτ O2) shortened significantly and Close time constants (τ c1 andτ c2 ) prolonged significantly in group C. ③ In group D,we compared the result between huobahuagen tablets and DXM, and got the same results. Conclusion L-L Ca channel activity increased significantly in asthma group. Huobahuagen tablets and DXM reversed the effect of asthma on L-L Ca channel. The effect of huobahuagen tablets and DXM on TSMC may be partly mediated via activation of L-L Ca channel.