三七总皂甙对突触体钙摄取功能的影响(英文)

Effect of saponins of Panax notoginseng on synaptosomal ^(45)Ca uptake

目的:研究三七总皂甙(PNS)的钙拮抗作用. 方法:大脑皮层突触体通过Ficoll密度梯度离心获取.用同位素测定的方法,观察体内或体外给药时,PNS对突触体钙摄取功能的影响. 结果:在50-800 mg·L^(-1)浓度范围内,PNS对钙摄取的抑制作用呈现量-效关系,IC_(50)=111(46-176)mg·L^(-1),并且对摄取过程的起始和最大反应相均有作用.PNS ip 200 mg·kg^(-1)具有类似反应.介质中的钙离子浓度影响PNS的上述作用.结论:PNS是神经元钙通道的阻滞剂.

AIM: To explore the calcium uptake antagonism of saponins of Panax natoginseng ( PNS ). METHODS: Synaptosomes were prepared from rat cerebral cortex by using differential Ficoll gradients. The effects of PNS on synaptosomal 45 Ca uptake were measured in vitro or after acute treatment. RESULTS: PNS 50 - 800 mg·L-1 produced a concentration-rated inhibition of Ca2+ uptake [IC50 = 111 (46 - 176) mg·L-1]. Both initial and maximal uptake were inhibited. Similar effect was obtained after acute PNS treatment with 200 mg·kg-1 ip. The blocking effect of PNS was reversed by calcium in media. CONCLUSION: PNS is a calcium channel blocker in neurons.