盐酸小檗碱对血管内皮M胆碱受体作用的研究

盐酸小檗碱在≤０．１μｍｏｌ／Ｌ浓度时，对乙酰胆碱松弛带内皮血管环的作用有剂量依赖性的增强；当浓度≥２０μｍｏｌ／Ｌ时，则对带内皮血管环具浓度依赖性的直接舒张作用，而去内皮或阻断Ｍ受体后均完全被抑制。本品还引起离体气管条的浓度依赖性收缩，而阿托品可竞争性地抑制此作用。放射配基一受体结合实验显示，Ｂｅｒ对大鼠唾液腺、大脑皮质和心脏的Ｍ受体均有中度亲和力

Effect of Berberine Hydrochloride on the Muscarinic Receptors on Endothelial Cells

In the endothelium intact thoracic arotic rings of rats, the relaxation induced by 10 mmol/L Acetylcholine (Ach) was potentiated by 0 001、0 01、0 1 μmol/L berberine hydrochloride (Ber) dose dependently.Above 20 μmol/L concentration, Ber relaxed the endothelium intact thoracic arotic rings directly.But these effects were totally abolished by pretreatment 10 μmol/L atropine, which blocked M Ach recepors.Ber induced contraction dose dependently on isolate helicine trips of guinea pig trachea, which was completely blocked by 10 μmol/L atropine.Atropine also caused the cumulative dose response curve for Ber to shift to the right parallel, without changing maximal response.The pA2 value was 9 79±0 42 ( n =8).In the radioligand receptor binding experiments, Ber binded to 3H QNB receptor with definite affinity in salivary gland, brain and heart.