不同浓度的咪唑安定对兔离体气管平滑肌收缩的影响

The effects of different concentrations of midazolam on the contraction of isolated rabbit tracheal smooth muscle

目的研究不同浓度的咪唑安定对离体气管平滑肌的舒张作用,以明确咪唑安定在10-5mol/L浓度时是否能够产生较为明显的舒张作用。方法用高浓度氯化钾、乙酰胆碱、电脉冲三种刺激因素诱发兔离体气管平滑肌收缩,并观察三种不同浓度的咪唑安定对其的影响。结果1.5×10-5mol/L的咪唑安定对三种刺激因素诱发的气管平滑肌收缩不产生明显抑制作用;1.5×10-4mol/L和3.0×10-4mol/L的咪唑安定可显著抑制上述三种刺激因素诱发的气管平滑肌收缩(P<0.05或P<0.01),普萘洛尔和中枢性苯二氮卓艹类受体阻断药氟马西尼不能拮抗咪唑安定对气管平滑肌的舒张作用。结论咪唑安定在10-5mol/L左右的浓度时对兔离体气管平滑肌收缩不能产生明显的抑制作用。

Objective To investigate the inhibitory effects of different concentrations of midazolam on the isolated rabbit tracheal smooth muscle. Methods KCl, ACh and electrical field stimulation were used for inducing the isolated rabbit tracheal smooth muscle contraction, on which the depressive effects of midazolam in different concentrations were studied. Results 1.5 ）〈 10^-5 mol/L of midazolam did not relax the tension. 1.5 × 10^-4 mol/L and 3.0×10^-4 mol/L of midazolam significantly depressed the tensions induced by the three stimulators （P〈 0. 05 or P〈0.01） in a concentration-related manner. Pretreatment with 4. 8 ）〈 10^-6 mol/L of beta adrenergic receptor blocker propranolol or 10^-5 mol/L of benzodlazepine receptor blocker flumazenil had no effects on tracheal smooth muscle relaxation induced by midazolam. Conclusion Midazolam at 10^-5 mol/L can not depress the tensions of isolated rabbit tracheal smooth muscle.