小檗胺松弛家兔离体回肠的作用

RELAXATION EFFECTS OF BERBAMINE ON THE ISOLATED RABBIT ILEUM

作者观察了小檗胺（Ｂｅｒ）对家兔离休回肠收缩反应的影响，并以钙拮抗剂维拉帕米（Ｖｅｒ）、硝苯啶（Ｎｉｆ）作对照。结果表明：Ｂｅｒ、Ｖｅｒ和Ｎｉｆ显著抑制回肠平滑肌自律性及Ａｃｈ（５μｍｏｌ／Ｌ）、Ｈｉｓ（５μｍｏｌ／Ｌ）诱导的收缩反应，上述作用呈剂量依赖关系；均非竞争性拮抗ＣａＣｌ２量－效曲线；在无钙营养液中，Ｂｅｒ３０μｍｏｌ／Ｌ、Ｖｅｒ３μｍｏｌ／Ｌ均明显抑制Ａｃｍ诱导回肠平滑肌两种收缩成份所致的收缩；Ｎｉｆ１μｍｏｌ／Ｌ仅抑制Ａｃｈ诱导的依内钙性收缩，对依外钙性收缩几无影响。提示：Ｂｅｒ有钙拮抗作用，其作用方式与Ｖｅｒ相似。

The effects of berbamine(Ber)on contraction response of the isolated rabbit ileum were studied, compared with verapamil(Ver) and nifidipine(Nif). Ber, Ver and Nif lowered the automaticity, and inhibited the contractions by low concentration of acetylcholine(Ach) and histamine(His).All of them noncompetitively antagonized CaCl2 cumulatlve dose-response curves, pD'2 values were 4.32±0.19,5.08±0.20, and5.98±0;31,respectively. Ber 30 μmol/L and Ver 3 μmol/L significantly inhibited the contractions of both responsecomponents induced by Ach; Nif 1 μmol/L only inhibited intracellular Ca2-dependent contraction evoked by Ach,but had little effect on extracellular Ca2+dependent contraction. These results indicate that Ber has a calcium antagonistic effect and is similar to Ver in mechanism.