蛇床子素对豚鼠离体心房的作用。

Effects of osthole on isolated guinea pig heart atria.

作者信息

Li L, Zhuang F E, Yang L, Zhang C L, Zhao G S, Zhao D K

机构信息

Institute of Clinical Pharmacology, Xi-an Medical University, China.

出版信息

Zhongguo Yao Li Xue Bao. 1995 May;16(3):251-4.

PMID:7660822

Abstract

AIM

To study the effects of osthole (Ost) on the isolated guinea pig atria and the relationship between Ost effect and Ca2+.

METHODS

Contractions of left atria were induced by electric stimulations. The contractile amplitude of left atria pre- and post-treated with Ost was measured according to the cumulative concentration method, the drug being added at 15 min intervals, the pA2 or pD2' were calculated. It were measured that the effects of Ost to the positive staircase and to the post-rest potential enhancement. The contractile responses were recorded via an auto-equiolibration recording instrument.

RESULTS

Ost 10-300 mumol.L-1 and Ver 0.1-30 mumol.L-1 decreased the contractile force and inhibited the isoprenaline-induced restoration of contractile response in the left atria rendered inexcitable by KCl 25 mmol.L-1. Ost and Ver antagonized the CaCl2- and isoprenaline-induced positive inotropic response noncompetively, the pD2' values to Ost were 4.41 +/- 0.13 and 4.90 +/- 0.15, to Ver were 6.53 +/- 0.22 and 6.91 +/- 0.17, respectively. Both of them inhibited the contraction of the left atrium and reversed the frequency-contraction response from positive to negative staircase in the higher dosage (500 and 1 mumol.L-1), but they showed only slight inhibitory effect on post-rest potentiation.

CONCLUSION

Ost was similar to, but much less potent than Ver in inhibiting the isolated guinea pig atria.

摘要

目的

研究蛇床子素（Ost）对豚鼠离体心房的作用及其作用与Ca2+的关系。

方法

采用电刺激诱发左心房收缩。按累积浓度法测定Ost预处理前后左心房的收缩幅度，每隔15分钟加药一次，计算pA2或pD2'。测定Ost对正阶梯现象和静息后电位增强的影响。通过自动平衡记录仪记录收缩反应。

结果

10 - 300μmol.L-1的Ost和0.1 - 30μmol.L-1的维拉帕米（Ver）降低了收缩力，并抑制了在25mmol.L-1 KCl作用下失去兴奋性的左心房中异丙肾上腺素诱导的收缩反应恢复。Ost和Ver非竞争性拮抗CaCl2和异丙肾上腺素诱导的正性肌力反应，Ost的pD2'值分别为4.41±0.13和4.90±0.15，Ver的pD2'值分别为6.53±0.22和6.91±0.17。两者在高剂量（500和1μmol.L-1）时均抑制左心房收缩并使频率 - 收缩反应从正阶梯变为负阶梯，但对静息后增强仅表现出轻微抑制作用。