(-),(+)-7-羟基-黄皮酰胺对大鼠海马齿状回突触传递功能的影响

Effects of (-), (+)-7-hydroxy-clausenamide on synaptic transmission in rat dentate gyrus in vivo

目的 观察 ( - ) ,( + ) 7 羟基 黄皮酰胺 ( 7 hydoxy clausenamide,7 OH Clau)对大鼠海马齿状回基础突触传递功能的影响。方法 细胞外记录低频刺激 ( 1 30Hz ,1 0mA)引起的海马齿状回群峰电位 (populationspike ,PS)。结果 侧脑室注入脑终浓度为 2× 10 - 6 mol·L- 1 ( - ) 7 OH Clau后 15 ,30 ,6 0min ,PS幅值比给药前均增加了 30 %以上 ,比空白对照组增加了 2 7%～ 4 1% ;而同剂量的 ( + ) 7 OH Clau在注射后的 3个时间点上 ,PS幅值比给药前下降了18%～ 2 5 % ,比空白对照组下降了 11%～ 2 0 %。结论 ( - ) 7 OH Clau能增强大鼠海马齿状回的基础突触传递活动 ,而 ( + ) 7 OH

Aim To investigate effects of (-), (+) 7 hydroxy clausenamide (7 OH Clau) on basal synaptic transmission in the dentate gyrus of anesthetized rats. Methods Extracellular recording of the population spike (PS) of hippocampal dentate gyrus following application of low frequency stimulation (1/30 Hz, 1 0 mA). Results Fifteen, thirty and sixty minutes after intracerebroventricular (icv) administration of an estimated final brain concentration of 2×10 -6 mol·L -1 , (-) 7 OH Clau caused over 30% increase relative to basal PS amplitude before administration, and 27%-41% increase relative to vehicle control ( P <0 05), while (+) 7 OH Clau exhibited 18%-25% and 11%-20% decrease in the PS amplitude when compared with basal PS amplitude and vehicle control ( P <0 05), respectively. Conclusion The basal synaptic transmission in the dentate gyrus of the rat hippocampus can be potentiated by (-) 7 OH Clau and attenuated by (+) 7 OH Clau, indicating that there was a stereoselective difference between the two enantiomers in the modulation of synaptic responses and plasticity.