小檗碱对神经递质引起的新生大鼠脑细胞内游离钙升高的影响

Effects of berberine on neurotransmitter induced intracellular free Ca 2+ elevation in isolated brain cells of neonatal rat 1

以Ｆｕｒａ－２／ＡＭ为荧光指示剂，利用ＡＲ－ＣＭ－ＭＩＣ阳离子系统测定小檗碱（Ｂｅｒ）对新生大鼠脑细胞静息Ｃａ２＋和神经递质引起的脑细胞内游离钙浓度（［Ｃａ２＋］ｉ）变化的影响．Ｂｅｒ１，１０，３０μｍｏｌ·Ｌ－１对脑静息［Ｃａ２＋］ｉ无明显影响．Ｂｅｒ１～１００μｍｏｌ·Ｌ－１剂量依赖的抑制谷氨酸引起的［Ｃａ２＋］ｉ升高．Ｂｅｒ１０μｍｏｌ·Ｌ－１能降低Ｈａｎｋｓ液有Ｃａ２＋和无Ｃａ２＋时去甲肾上腺素引起的［Ｃａ２＋］ｉ升高，且能降低５－羟色胺引起的［Ｃａ２＋］ｉ升高（在细胞外液有Ｃａ２＋时）．结果提示Ｂｅｒ可降低谷氨酸，去甲肾上腺素和５－羟色胺引起的［Ｃａ２＋］ｉ升高，这可能是其抗脑缺血机理之一．

Effects of berberine(Ber) on resting free intracellular Ca 2+ level and neurotransmitters induced rise in brain [Ca 2+ ] i of newborn rats were studied with Ca 2+ sensitive fluorescent indicator(Fura 2/AM) using AR CM MIC cation measurement system. No significant effects of Ber(1, 10, and 30 μmol·L 1 ) on resting brain [Ca 2+ ] i level were observed. Ber 1-100 μmol·L 1 concentration dependently inhibited L glutamate induced [Ca 2+ ] i elevation. Ber 10 μmol·L 1 significantly inhibited norepinephrine induced increase in brain [Ca 2+ ] i in the presence of Ca 2+ 1.3 mmol·L 1 and Ca 2+ free medium, and in Hanks solution with 1.3 mmol·L 1 of calcium, 5 hydroxytryptamine induced elevations in brain [Ca 2+ ] i were reduced by Ber 10 μmol·L 1 . The results suggest that the inhibitory actions of Ber on brain [Ca 2+ ] i elevation induced by glutamate, norepinephrine, or 5 hydroxytryptamine may be related to its protective brain ischemia.