藻酸双酯钠对局灶性脑缺血再灌注大鼠脑内钙离子浓度的影响

The neuroprotection of polysaccharidesulfate in the experimental cerebral ischemia

目的探讨藻酸双酯钠(polysaccharidesulfate,PSS)对局灶性脑缺血再灌注大鼠脑组织神经细胞凋亡的保护机制。方法经大鼠颈内动脉将一线栓插入右侧大脑中动脉1.5h后再灌注24h制成局灶性脑缺血再灌注大鼠模型;在再灌前30min或再灌后5h经腹腔给予不同剂量的藻酸双酯钠或赋形剂;用流式细胞术测量受损脑组织神经元内钙离子浓度及凋亡率,同时观察大鼠的神经功能缺损评分。结果藻酸双酯钠治疗组神经功能缺损较非治疗组明显减轻,相应的藻酸双酯钠治疗组细胞内钙离子浓度增高受抑、细胞凋亡减少;不同时间点给药组间上述指标亦有显著性差异。结论藻酸双酯钠可以减轻脑组织神经元再灌注损伤和抑制神经元凋亡;抑制受损神经元胞内钙离子浓度增高是其保护作用的可能机制。

Objective To study the protective effect of PSS on cell apoptosis in focal cerebral ischemia-reperfusion injury rats. Methods Right middle cerebral artery was occluded by inserting a thread through internal carotid artery for 90 minutes and then reperfused for 24 h. Different doses of PSS were injected via intraperitoneal of the rats at 30 minutes before reperfusion or 5 hours after reperfusion. Intra-cellular freecalcium [Ca 2+ ]_i and rates of both apoptosis and death were measured by flow cytometry (FCM). The behavior of rats was investigated at the same time. Results The damage of rat's behavior in the PSS-treatment groups was mild in comparison with untreated group. The numbers of apoptosis cells were dramatically reduced in the PSS-treatment groups in comparison with untreated group. While the increasing [Ca 2+ ]_i was reduced by PSS. These significant difference between 30 minutes before onset and 5 h after reperfusion groups was also discovered. Conclusions PSS can alleviate the neuronal damage and inhibite apoptosis induced by ischemia-reperfusion. The anti-apoptosis effects may be attributed to its effects by inhibiting the increasing of [Ca 2+ ]_i.