白藜芦醇抑制大鼠海马CA1区神经元放电(英文)  

Resveratrol inhibits neuronal discharges in rat hippocampal CA1 area

作　　者：李明[1] 王庆山[1] 陈怡[2] 王泽民[1] 刘政[1] 郭淑梅[1] 

机构地区：[1]河北医科大学基础医学研究所生理室,石家庄050017 [2]河北医科大学基础医学研究所病理学教研室,石家庄050017

出　　处：《生理学报》2005年第3期355-360,共6页Acta Physiologica Sinica

摘　　要：应用细胞外记录单位放电技术,在大鼠海马脑片上观察了白藜芦醇(resveratrol)对海马CA1区神经元放电的影响。实验结果如下:(1)在52个CA1区神经元放电单位给予白藜芦醇(0.05、0.5、5μmol/L)2min,有46个放电单位(88.5%)放电频率明显降低,且呈剂量依赖性;(2)预先用0.2mmol/L的L-glutamate灌流海马脑片,8个放电单位放电频率明显增加,表现为癫痫样放电,在此基础上灌流白藜芦醇(5μmol/L)2min,其癫痫样放电被抑制;(3)预先用L型钙通道开放剂BayK8644灌流7个海马脑片,有6个单位(85.7%)放电增加,在此基础上灌流白藜芦醇(5μmol/L)2min,其放电被抑制;(4)9个放电单位灌流一氧化氮合酶抑制剂L-NAME(NG-nitro-L-argininemethylester)50μmol/L,有7个单位(77.8%)放电明显增加,在此基础上灌流白藜芦醇(5μmol/L)2min,放电被抑制;(5)10个放电单位灌流大电导钙激活性钾通道阻断剂TEA(tetraethylammoniumchloride)1mmol/L后,有9个单位(90%)放电增加,在此基础上灌流白藜芦醇(5μmol/L)2min,8个放电单位(88.9%)放电频率明显减低。以上结果提示:白藜芦醇能抑制海马神经元自发放电以及由L-glutamate、L-NAME、BayK8644和TEA诱发的放电,可能与白藜芦醇抑制L型钙通道,减少钙内流有关;似乎与大电导钙激活性钾通道无关。The effects of resveratrol on the discharges of neurons in CA1 area of rat hippocampal slices were examined by usingextracellular recording technique. The results are as follows: (1) In response to the application of resveratrol (0.05, 0.5, 5.0 μmol/L,n=52) into the superfusate for 2 min, the spontaneous discharge rate of 46/52 (88.5%) neurons was significantly decreased in a dose-dependent manner; (2) Application of L-glutamate (0.2 mmol/L) into the superfusate led to a marked increase in discharge rate of all 8(100%) slices in an epileptiform pattern. The increased discharges were suppressed by application of resveratrol (5.0 μmol/L); (3) In7 slices, perfusion of the selective L-type calcium channel agonist, Bay K8644 (0.1 μmol/L), induced a significant increase in thedischarge rate of 6/7 (85.7%) slices. The increased discharges were suppressed by application of resveratrol (5.0 μmol/L); (4) In 9 slices,perfusion of nitric oxide synthase (NOS) inhibitor NG-nitro-L-arginine methyl ester (L-NAME, 50 μmol/L) into the superfusatesignificantly augmented the discharge rate of 7/9 (77.8%) slices. Resveratrol (5.0 μmol/L) applied into the superfusate reduced theincreased discharges of all 7/7 (100%) neurons; (5) In 10 units, the large-conductance Ca2+-activated K+ channel blocker(tetraethylammonium chloride, TEA, 1 mmol/L) significantly increased the discharge rate of 9/10 (90%) slices. Resveratrol (5.0 μmol/L) applied into the superfusate inhibited the discharges of 8/9 (88.9%) slices. These results suggest that resveratrol inhibits theelectrical activity of CA1 neurons. This effect may be related to the blockade of L-type calcium channel and a subsequent reduction ofcalcium influx, and probably has no association with large-conductance Ca2+-activated K+ channel.

关 键 词：海马 白藜芦醇 钙通道 

分 类 号：R285[医药卫生—中药学]