摘要
目的采用离体心房灌流模型观察和探讨黄芪水提液对家兔心房机械活动的影响及其机制。方法将大耳白兔耳缘静脉注射乌拉坦(20 mg/kg)麻醉后,立即开胸取出心脏,剥离左心房迅速固定在心房灌流装置上,并给予适宜的电刺激使心房搏动,利用生理记录仪持续记录相关药液影响下的心房搏动压的变化,并读取每搏输出量。结果黄芪水提取液具有增强心房搏动压及心房搏出量的作用;逆向Na+-Ca2+交换体抑制剂KB-R 7943可以阻断黄芪水提取液导致的心房搏动压和搏出量增多的效应;L-型Ca2+通道阻断剂硝苯地平不但可以阻断黄芪水提取液导致的心房搏动压和搏出量增多的效应,而且使心房搏动压和搏出量进一步受到抑制。结论黄芪水提取液主要通过Na+-Ca2+交换体及L-型Ca2+通道引起家兔心房的正性肌力效应。
Objective To study the effect and mechanism of Radix Astragali extract on atrial dynamics in peffused beating rabbit atria. Methods The rabbits were anesthetized and removed the heart. The left atrium was isolated and fixed on the atrial peffusion system and paced by electrical stimulation. Atrial pulse pressure was measured via a pressure transducer connected to the intra - atrial catheter and recorded on a physiograph. The changes in atrial stroke volume were monitored by reading the lowest level of the water column in the calibrated atrial cannula during end diastole. Results Radix Astragali extract increased rabbit atrial dynandos KB -R 7943, an inhibitor of reversed Na^＋ -Ca^2＋ exchanger, blocked the effect of Radix Astragali extract on atrial dynamics, Nifedipine, a L - type Ca^2 ＋ channel inhibitor, also blocked the augmentation of atrial dynamics induced by Radix Astragoli exuract and showed a negative inotropic effect. Conclusion Radix Astragali extract can increase rabbit atrial dynamics via Na^＋ Ca^2＋- exchanger and L- type Ca^2＋ channel.
出处
《时珍国医国药》
CAS
CSCD
北大核心
2008年第9期2115-2117,共3页
Lishizhen Medicine and Materia Medica Research
基金
吉林省中医药管理局中医药科技项目资助(No.zy23)
