摘要
目的:研究盐酸小檗碱对乙酰胆碱系统的影响。方法:采用离体血管环、离体支气管螺旋体及放射配基受体结合实验等方法。结果:较低浓度的盐酸小檗碱(Ber)对乙酰胆碱的舒张反应有浓度依赖性的增强作用;而较高浓度的Ber可浓度依赖性地直接舒张带内皮的动脉环,此作用在去内皮或阻断M受体后被完全抑制。在豚鼠离体气管条上,Ber可引起浓度依赖性的收缩反应,而阿托品可阻断这种作用。放射配基受体结合实验显示盐酸小檗碱可特异性与大鼠脑组织的毒蕈碱受体结合,Ki值为16μmol·L-1。结论:盐酸小檗碱可激动毒蕈碱受体,从而引起血管的内皮依赖性的舒张反应及支气管的收缩。
AIM:
To study the effect of berberine hydrochloride(Ber) on muscarinic receptors. METHODS: Use
isolated arotic rings, isolated helical trachea strips and radioligandreceptor binding experiment.
RESULTS: The inhibitory action of acetylcholine(ACh) on the contractile response of KCl in the
endotheliumintact thoracic arotic rings of rats was potentiated by Ber concentrationdependently.
At concentrations above 20 molL-1, Ber relaxed the endotheliumintact rings directly. The EC50
value was 315 molL-1. But such inhibitory action of Ber was totally abolished by removing the
endothelium or by pretreatment with atropine 10 molL-1. Ber dosedependently induced
contraction on isolated helical strips of guinea pig trachea. This action was completely blocked
by atropine 10 molL-1. In the radioligandreceptor binding experiments, Ber was shown to bind
to muscarinic receptors with definite affinity in rat brain. The Ki value was 16 molL-1.
CONCLUSION: Ber is an agonist of muscarinic receptor. It may release EDRF from vascular
endothelia cells by exciting muscarinic receptors to relax arotic rings.
出处
《药学学报》
CAS
CSCD
北大核心
1999年第4期260-263,共4页
Acta Pharmaceutica Sinica
基金
广东省自然科学基金
关键词
盐酸小檗碱
毒蕈碱受体
乙酰胆碱
berberine
hydrochloride
muscarinic receptors
acetylcholine