三七皂甙对大脑中动脉栓塞性脑缺血的影响

目的 观察三七皂甙(PNS)及三七皂甙单体(Rb₁、Rg₁)对大脑中动脉栓塞(MCAO)后脑血流量(CBF)及脑组织超微结构的影响。方法 60只Wistar大鼠随机分7组:其中第7组为假手术对照组(SO);第1组为MCAO对照组;第2,3,4组MCAO前30min及MCAO后即刻分别静脉给予Rg₁20μg·kg^-1,Rb₁20μg·kg^-1,Nim5μg·kg^-1;第5,6组分别于MCAO前灌胃PNS200mg·kg^-1及400mg·kg^-1连续10d。结果 与MCAO对照组比较Rb₁,Nim,PNS400mg·kg^-1组,CBF明显增高(P<0.01),Rg₁组CBF无明显增加。PNS能明显提高超氧化物歧化酶(SOD)活力,降低一氧化氮(NO)含量。超微结构显示,Rb₁,Rg₁,PNS和Nim能明显减轻脑缺血性神经元损伤,其中Rb₁,Nim,PNS400mg·kg^-1组优于Rg₁和PNS200mg·kg^-1组。结论 Rb₁,Nim和PNS400mg·kg^-1能明显增加MCAO区CBF,其机理可能与扩张血管有关;Rg₁不能增加CBF。Rb₁,Rg₁,PNS有减轻脑缺血坏死作用。其机理可能与提高脑细胞内SOD活力、降低细胞内Ca²⁺及NO含量有关。

Effect of PNS on MCAO-induced cerebral ischemia

Aim The Effect of panax notoginseng(PNS)andits monomers Rb₁ and Rg₁ on cerebral blood f low (CBF)in rats with middle cerebral artery occlusion(MCAO)was observed.Methods Sixty Wistarrats wererandomizedinto 7 groups, which weresubdividedinto 5 MCAO experimental groups and one MCAO control group operated via internal artery and one sham-operated(SO) control group undergone the samesurgical procedurebut without MCAO.3 MCAO experimental mental groups weregiven different drugs respectively in the doses of Rg₁ 20 μg·kg^-1 (iv);Rb₁ 20 μg·kg^-1 (iv)and nimodipine.Nim 5 μg·kg^-1 (iv)30 minutes beforeandimmediately after MCAO.Ano ther 2 MCAO groups weregiven PNS(200 mg·kg^-1 or 400 mg·kg^-1, po.)for 10 days and MCAO was observed 30 minutes after the final administration.Results CBF in Rb₁ group, Nim group and PNS group was increased signi ficantly (P<0.01), as compared with thatin the MCAO control group, whereas in Rg₁ group it was decreased obviously(P<0.05).Electron microscopic structural analysis indicated that Rb₁, Rg₁, PNS and Nim obviously alleviated brain injury and neuron necrosis caused by ischemia.The samedosage of PNScould markedly increase the action of superoxide dismutase (SOD)and decrease the concentration of nitrie oxide(NO).Conclusion Different from Rg₁, Rb₁ and PNScan increase CBF in MCAO region.Allthese drugs can lessen brain injury and neuron necrosis.The mechanismmay berelated to thereduction of Ca²⁺and NO contentin ischemic reg ion.