人参皂苷Rg1对铅所致大鼠海马CA1区长时程增强损伤的影响(英文)

Effect of ginsenoside Rg1 on long-term potentiation impaired by lead in CA1 region of rat hippocampus

目的研究人参皂苷Rg1对铅引起的大鼠海马CA1区长时程增强(LTP)的损伤是否有修复作用。方法 Wistar大鼠从出生至断奶通过母乳摄入铅(母鼠每天饮用0.2%醋酸铅溶液20 mL),在出生后的20 ～25 d记录其海马CA1区兴奋性突触后电位并诱导长时程增强。结果人参皂苷Rg1 (50μmo.lL-1)灌流对照组和铅暴露组大鼠海马脑片20min均能诱导出LTP,铅暴露组大鼠的LTP幅度较对照组低。在铅暴露组大鼠的海马脑片上,高频刺激(HFS,1 s, 100 Hz)诱导的LTP较对照组显著降低, 50μmol.L-1人参皂苷Rg1灌流20 min,HFS诱导的LTP幅度提高47.1%。结论人参皂苷Rg1能够提高基础的突触传递,并能部分修复铅损伤的HFS-LTP。

AIM To investigate whether ginsenoside Rgl can reverse chronic lead-induced impairment of long-term potentiation （LTP） in the CA1 region of rat hippocampus. METHODS Neonatal Wistar rats were exposed to lead from parturition to weaning via milk of dams whose drinking water （20 mL per day） contained 0.2% lead acetate. Field excitatory postsynaptic potentials （fEPSP） were recorded and LTP was induced in the CA1 region in rat hippocampal slices on postnatal 20 -25 d. RESULTS In hippocampal slices from both control and lead-exposed rats, perfusion with ginsenoside Rgl 50 μmol·L^-1 for 20 min induced enhancement of fEPSP （LTP）, while the amplitude of LTP in lead-exposed rats was lower than that of controls. In hippocampal slices from chronic lead-exposed rats, LTP induced by high-frequency stimulation （HFS, 1s, 100 Hz） was significantly reduced, while perfusing with ginsenoside Rgl （50 μmol·L^-1） for 20 min increased the amplitudes of LTP induced by HFS by 47.1%. CONCLUSION Rgl can increase basic synaptic transmission and partially reverse chronic lead-induced impairment of HFS-LTP.