救脑宁注射液对谷氨酸、5-羟色胺诱发大鼠皮质神经细胞内游离钙超负荷的影响

Effect of Jiunaoning Iujection on Overload of Intracellular Free Calcium of Cerebral Cortex Induced by Glutamic Acid or 5-Hydroxytryptamine in Fetal Rats

目的：探讨救脑宁注射液对谷氨酸（Glu）、5-羟色胺（5-HT）诱发大鼠皮质神经细胞内游离钙（〔Ca2+〕i）超负荷的影响。方法：以Fura-2／AM为细胞内钙离子的荧光指示剂，用双波长荧光分光光度计测定了急性分离的新生大鼠神经细胞〔Ca2+〕i的变化，观察Glu、5－HT对〔Ca2+〕i的影响及救脑宁注射液的干预作用。结果：Glu和5－HT剂量依赖性引起〔Ca2＋〕i增加，导致细胞内钙超载；救脑宁注射液可显著降低细胞内钙的升高，保护神经细胞免受Glu和5－HT的损害。结论：救脑宁注射液对中风病的治疗作用与其对抗Glu、5－HT等毒性物质的作用，抑制受体依赖性钙通道的开放，减少外钙的流入，有效地防止钙超载等机制有关。

Objective: To explore the effect of Jiunaoning Injection (JNNI) on overload of intracellular free calcium of cerebral cortex induced by glutamic acid or 5-hydroxytryptamine (5-HT) in fetal rats. Methods: Double wave length spectrofluorometer with Fura-2/AM as the fluorescence indicator for intracellular calcium ions (〔Ca2+〕i) was used to measure the changes of 〔Ca2+〕i in instantly separated cortical nerve cells of newborn rats affected by glutamic acid or 5-HT, as well as the interference of JNNI on it. Results: Glutamic acid or 5-HT could elevate the intracellular 〔Ca2+〕i dose-dependently and induce 〔Ca2+〕i overload. JNNI could restrain the elevation markedly so as to protect the neurocytes from injury of glutamic acid and 5-HT. Conclusion: The therapeutic ef fect of JNNI in treating apoplexy is related with its action in suppressing the toxic substances as glutamic acid and 5-HT, restraining the opening of receptor dependent calcium channel, reducing the external cellular calcium influx and preventing the calcium overload effectively.