银杏叶提取物及其主要成分白果内酯对不同年龄大鼠胸主动脉环的舒张作用

Vasorelaxation effect of ginkgo biloba extract and bilobalide on thoracic aorta ring of rats in different ages

目的:观察和比较银杏叶提取物(GBE)和白果内酯对不同年龄大鼠动脉环的舒张作用。方法:4～24周SD大鼠的胸主动脉环被固定在组织浴槽内,先给予去甲肾上腺素预收缩,稳定后给予各浓度的试验药物,观察其对动脉环舒张作用。结果:(1)GBE和白果内酯对不同年龄大鼠去甲肾上腺素预收缩的腹主动脉环均有舒张作用,并具有剂量-效应关系。对4周大鼠舒张效应,GBE从(1.02±0.21)%(0.01mg/mL)上升到(27.62±3.62)%(1mg/mL),白果内酯从(2.53±0.83)%(1μmol/L)上升到(22.03±3.14)%(100μmol/L)。(2)随着大鼠年龄的增长,GBE和白果内酯对胸主动脉环的舒张效应逐渐降低,白果内酯对老龄大鼠胸主动脉环的舒张效应下降更加明显。对4周到24周大鼠舒张效应,1mg/mLGBE从(27.62±3.62)%降到(14.79±3.67)%(P<0.05),100μmol/L白果内酯从(22.03±3.14)%降到(6.23±2.16)%(P<0.05)。1mg/mLGBE对24周大鼠胸主动脉环的舒张效应(14.79±3.67)%明显高于100μmol/L白果内酯(6.23±2.16)%,P<0.01。结论:一定浓度的GBE和白果内酯对大鼠动脉环的舒张效应随着大鼠年龄的增长而降低,并且,白果内酯对老龄大鼠动脉环的舒张效应下降更加明显。

Objective To observe the vasorelaxation effect of ginkgo biloba extract （GBE） and bilobalide on thoracic aorta ring of rats in different ages. Methods Thoracic aorta ring, which was isolated from 4-24 weeks old SD rats, were fixed in Krebs-Henseleit solution and were administered with norepinephrine （NE） to produce stabile contraction, then different doses of GBE and bilobalide were given to observe its vasorelaxation effect. Results （ 1 ）GBE and bilobalide can dose-dependently relax NE-induced constriction. On 4-week-old rats, the vasorelaxation effect of GBE was increased from （1.02 ± 0.21）% at 0.01 mg/mL to （27.62 ± 3.62）% at 1 mg/mL; that of bilobalide was increased from （2.53 ± 0.83）% at 1 μmol/L to （22.03 ± 3.14）% at 100 μmol/L. （2）Vasorelaxation effect of GBE and bilobalide was generally decreased with aging, further more was observed of bilobalide. On 4-24 weeks old rats, the vasorelaxation effect of GBE at lmg/mL was decreased from （27.62±3.62）% to （14.79± 3.67）% （P 〈 0.05）; that of bilobalide at 100 p, mol/L was decreased from （22.03 ± 3.14）% to （6.23 ± 2.16）% （P 〈 0.05）. In 24-week-old rats, the vasorelaxation effect of GBE at lmg/mL was higher than that of bilobalide at 100 μmol/L [（14.79± 3.67）% vs （6.23 ±2.16）%] （P 〈 0.01）. Conclusion Vasorelaxation effect of GBE and bilobalide on thoracic aorta ring of rats was generally decreased with aging, further more was observed of bilobalide.