小檗碱对培养大鼠神经细胞内游离Ca2+的影响

以Fura-2/AM为细胞内钙离子的荧光指示剂,用AR-CM-MIC阳离子测定系统,直接测定了体外培养的新生大鼠神经细胞内游离钙(Ca²⁺]i)值,并观察了小檗碱(Ber)的影响。结果表明,Ber对神经细胞静息Ca²⁺]i无明显影响,Ber1～100μmol·L^-1能剂量依赖地抑制去甲肾上腺素和H₂O₂引起的Ca²⁺]i升高,其IC₅₀分别为39.9和17.9μmol·L^-1。高剂量Ber(10～100μmol·L^-1)能抑制高K+引起的Ca²⁺]i升高。姐果提示,Ber对去甲肾上腺素,高K⁺及H₂O₂引起的Ca²⁺]i升高的抑制作用可能是其抗脑缺血作用机制之一。

EFFECT OF BERBERINE ON INTRACELLULAR FREE CA2+ CONCENTRATION IN CULTURED BRAIN CELLS

Intracellular free calcium concentration (Ca²⁺ ]i) was measured with Ca²⁺ sensitive fluorescent indicator, Fura-2/AM, in cultured brain cells using AR-CM-MIC cation measurement system, and the effects of berberine(Ber) on the changes in Ca²⁺]i induced by CaCl₂, norepinephrine, KCl and H₂O₂ were studied. The results indicate that the resting Ca²⁺]i was 35±8 nmol·L^-1 in Ca²⁺ free Hank′s solution. Ber showed no effect on the resting Ca²⁺]i when the extracellular Ca²⁺ were 0.01～10 mmol·L^-1 . Ber 1～100 μmol·L^-1 dose dependently inhibited norepinephrine and H₂O₂ induced Ca²⁺ ]i elevation. Ber at high concentration(10～100 μmol·L^-1) inhibited K⁺ induced Ca²⁺ ]i elevation. This suggests that the inhibitory effects of Ber on norepinephrine, K⁺, and H₂O₂ induced Ca²⁺]i elevation may be one of the mechanisms against cerebral ischemia.