目的 考察羚貝止咳糖漿對豚鼠離體氣管螺旋條平滑肌收縮的抑制作用，并探討其作用機制。方法 制備豚鼠離體氣管平滑肌螺旋條，隨機分為羚貝止咳糖漿組、川貝雪梨糖漿組和異丙腎上腺素組，每組各3例。加入0.167 μg/mL氯化乙酰膽堿制備豚鼠離體氣管螺旋條平滑肌收縮模型。當氣管平滑肌張力達到最高點時，觀察羚貝止咳糖漿最大有效濃度對豚鼠離體氣管螺旋條收縮作用的影響，計算抑制率。采用RT-PCR法檢測豚鼠離體氣管條肌球蛋白輕鏈激酶（MLCK）mRNA表達，采用疫蛋白印跡法（Western blotting）法檢測豚鼠離體氣管條MLCK蛋白表達情況。結(jié)果 羚貝止咳糖漿能夠顯著抑制氯化乙酰膽堿引起的豚鼠氣道平滑肌過度收縮，松弛氣道平滑肌，作用強度強于川貝雪梨糖漿（P<0.05），但弱于異丙腎上腺素（P<0.01）。羚貝止咳糖漿能夠顯著降低由氯化乙酰膽堿引起的過度收縮的豚鼠氣道平滑肌中MLCK mRNA表達、MLCK的蛋白表達量（P<0.01）。結(jié)論 羚貝止咳糖漿可能通過減少處于過度收縮狀態(tài)的平滑肌MLCK mRNA、MLCK蛋白的表達量，起到松弛氣道平滑肌、解除氣道痙攣的作用，從而發(fā)揮其止咳平喘的作用。

Objective To study inhibition of Lingbei Zhike Syrup on contraction of smooth muscle of tracheal spiral strips in guinea pig, and explore its mechanism. Methods Tracheal spiral lines in guinea pig were isolated and prepared, and were randomly divided into Lingbei Zhike Syrup group, Chuanbei Xueli Syrup group, and isoproterenol group, and each group had three tracheal spiral strips. Acetylcholine chloride (0.167 μg/mL) was used to prepare contraction models of smooth muscle of tracheal spiral strips in guinea pig. When tension was the maximum, effects of Lingbei Zhike Syrup with maximum concentration on contraction of smooth muscle of tracheal spiral strips in guinea pig were observed, and inhibition rates were calculated. RT-PCR method was used to detect the expressions of myosin light chain kinase (MLCK) mRNA. Western blotting method method was used to detect expressions of MLCK protein in guinea pig. Results Lingbei Zhike Syrup could inhibit excessive contraction of airway smooth muscle induced by acetylcholine chloride, and relax airway smooth muscle. The effect of Lingbei Zhike Syrup was stronger than that of Chuanbei Xueli Syrup (P < 0.05), but weaker than that of isoproterenol (P < 0.01). Lingbei Zhike Syrup could significantly decrease the expression of MLCK mRNA expression and MLCK protein in airway smooth muscle with excessive contraction in guinea pigs induced by acetylcholine chloride. Conclusion Lingbei Zhike Syrup can reduce expression of MLCK mRNA and MLCK protein in excessive contraction of smooth muscle, relax airway smooth muscle, and relieve airway spasm, and has antitussive and antiasthmatic effect.

吉林省科技發(fā)展計劃項目（20150311113YY）