葡萄籽原花青素舒张家兔离体主动脉的研究

目的研究葡萄籽原花青素(PC)对主动脉环的舒张作用及机制。方法采用家兔离体主动脉平滑肌标本,以去甲肾上腺素(NA)预收缩主动脉后给予不同剂量PC观察其张力变化,并探讨去除血管内皮、给予NO合酶抑制剂左旋硝基精氨酸(L-NNA)、甲烯蓝(M B)、环氧酶抑制剂吲哚美辛(Indo)和β肾上腺素能受体阻断剂普萘洛尔(P rop)对血管张力变化的影响。结果PC对动脉环静息张力无明显影响,但不同剂量PC可使1×10-6m o l/L NA预收缩的血管出现明显地舒张(r=0.63,P<0.001)。去除血管内皮、1×1-0 4m o l/L L-NNA或1×10-5m o l/L M B可减弱PC的舒张作用,但Indo和P rop无影响。另外,40μg/mL PC对无内皮血管环NA和KC l的量效收缩反应明显减弱,且NA和KC l的PD2分别由对照组的7.05±2.19和1.57±1.37降低为6.04±1.77和1.01±0.93。结论PC对主动脉的舒张作用是通过平滑肌细胞膜上的受体依赖性C a2 通道和电压依赖性C a2 通道抑制C a2 内流,使动脉环舒张,其作用与内皮释放的NO有关。

Vasodilation of procyanid ins from grape seeds on isolated rabbit aorta

Objective To study the effects of sinomenine on scavenging oxygen free radical and anti-lipid peroxidation in vitro. Methods Superoxide anion free radical(O_2~÷) induced by the auto-oxidation of pyrogallol and hydroxyl free radical(OH) induced by Fenton system were determined by spectrophotometry.The inhibition on homogenate and mitochondrial lipid peroxidation,malondialdehyde(MDA),of rat liver induced by VC-Fe(2+) system was measured by thiobarabituric acid(TBA) colorimetric method.Results Sinomenine could significantly scavenge O2~÷ and ·OH,it's EC_(50) were 1.35 and 0.136 mg/mL respectively.Sinomenine could also remarkably inhibit the lipid peroxidation of rat liver homogenate and mitochondria induced by auto-oxidation and VC-Fe(2+) system.The scavenging and inhibitory effect exhibited in a concentration-dependent manner.Conclusion The Results indicate that sinomenine possesses the effect of scavenging oxygen free radicals and anti-lipid peroxidation,which shows the protection of liver mitochondria