Vasodilative activity of levamlodipine in isolated rat basilar artery and its underlying mechanisms
10.3760/cma.j.issn.1671-8925.2015.05.002
- VernacularTitle:左旋氨氯地平对预收缩的大鼠离体基底动脉的舒血管活性作用及其机制研究
- Author:
Yangxin PAN
1
;
Yuanyuan SHI
;
Jian CHEN
;
Sheng TAN
Author Information
1. 增城市永宁街宁西社区卫生服务中心
- Keywords:
Levamlodipine;
Hypoxia;
Basilar artery;
Vasodilative activity
- From:
Chinese Journal of Neuromedicine
2015;14(5):438-442
- CountryChina
- Language:Chinese
-
Abstract:
Objective To explore the effect of levamlodipine on contraction of isolated rat basilar arteries induced by 5-hydroxytryptamine (5-HT) in hypoxic condition and its mechanism.Methods Basilar arteries in SD rats were applied in this experiment,and divided into vascular endothelial group and endothelium intact group,and the arteries in the vascular endothelial group were perfused low ionic strength solution to remove the vascular endothelium.Mixed gases were passed continuously into the bath liquid during the experiment;according to the different objectives,95% O2+5% CO2 mixed gas was passed at normoxia condition,while 95% N2+5% CO2 gas mixture at hypoxia.Blood vessels from the two groups were carried out vascular endothelial integrity and stability test.After passing the test,5× 10-7 mol/L 5-HT was used to pre-contract blood vessel;(1) vessels were respectively incubated with different concentrations (10-8-10-3 mol/L) of levamlodipine for 15 min,and the diameter changes of vessels were determined at each time point using vascular tension system;(2) 10-4 mol/L L-NAME solution (nitric oxide synthase inhibitor) for 30 min at hypoxia and 10-4 mol/L of amlodipine for 15 min at normoxia condition were incubated into the vessels,respectively,and the diameter changes of rat basilar artery precontracted by 5-HT were also recorded.Results (1)The inhibitory percentage of levamlodipine at different concentration (10-8-10-3 mol/L) in the endothelium intact group was 0.0436%± 0.0116%,0.0530%±0.0134%,0.0696%±0.0103%,0.1265%±0.0284%,0.2362%±0.0275%,0.4084%± 0.0260%,0.5185%±0.0238% and 0.5358%±0.0160%,respectively,and that in the vascular endothelial group was 0.0607%±0.0084%,0.0852%±0.0138%,0.1676%±0.0247%,0.3285%±0.0250%,0.4161%± 0.284% and 0.4219%±0.260%;the inhibiting effect in the endothelium intact group was more obvious than that in the vascular endothelial group at hypoxic condition with significant difference (P<0.05).(2) At the normal condition,the inhibitory percentage of levamlodipine was 0.9626%±0.0224% and 0.7358% ± ±0.0149% before and after L-NAME treatment;at the hypoxic condition,the inhibitory percentage of levamlodipine was 0.9485%±0.0129% 、0.8979%±0.0150% before and after L-NAME treatment;the difference between the two conditions were significantly different (P<0.05) Conclusion Levamlodipine has concentration-dependent inhibitory effects on vasoconstriction of rat basilar artery induced by 5-HT in hypoxic condition,which may be related to receptor-operated calcium channels and the release ofendothelium derived relaxing factor NO.