银杏叶总黄酮对豚鼠肠系膜下神经节细胞ls-EPSP的影响  

Effect of the total flavonoids of ginkgo on the neurons of inferior mesenteric ganglion of guinea pig in vitro

作　　者：黄九龙[1] 胡金兰[1] 孔淼[1] 王烈成[1] 吴政[1] 柯道平[1] 李忠稳[1] 马嵘[1,2] 孔德虎[1] 

机构地区：[1]安徽医科大学生理学教研室,神经生理研究室,合肥230032 [2]美国德州北方大学卫生科学中心生理学系

出　　处：《安徽医科大学学报》2006年第6期655-659,共5页Acta Universitatis Medicinalis Anhui

基　　金：安徽省教育厅自然科学基金资助项目(编号:2006KJ362B;2005KJ263)

摘　　要：目的观察银杏叶总黄酮（TFG）对交感神经节细胞迟慢兴奋性突触后电位（ls-EPSP）的影响并分析其作用的可能机制。方法细胞内记录技术和离体神经节灌流。结果豚鼠肠系膜下神经节（IMG）细胞静息电位为（-53．1±6．5）mV（n=54）；重复电刺激（10V，1ms，20Hz，4s）与IMG相连的腹下神经，在IMG有61．1％（33／54）的细胞可诱发ls-EPSP，其电位的幅度与时程分别为（7．7±1．8）mV和（97．4±17．4）s（n=33）；用TFG（100～500mg／L）灌流，其中有78．8％（26／33）细胞的ls-EPSP出现抑制，幅度与时程均表现降低和缩短，且表现一定的剂量依赖性；另有21．2％（7／33）的细胞无明显反应。由TFG引起的ls-EPSP抑制可被低钙／高镁Krebs液可逆性阻断，但不受胆碱或肾上腺素受体阻断剂影响；亦可被低钠（58mmol／L）、高钾（20mmol/L）的Krebs液和河豚毒（10μmol／L）所增强，并可被四乙基铵（1mmol／L）所减弱。结论TFG可不同程度抑制IMG内大多数细胞的ls-EPSP，其作用离子机制可能与Na^＋内流减弱和K^＋外流增强有关。Objective To investigate and analyze the effect of the total flavonoids of ginkgo （TFG） on the late slow excitatory postsynaptic potential （ls-EPSP） of the neurons of inferior mesenteric ganglion （IMG） of guinea pig in vitro. Methods intracellular microelectrode recording and administration of superfusion. Results The mean value of resting potential （RP） of neurons of IMG of guinea pig was （ - 53.1 ± 6. 5 ） mV （ n = 54 ）. Repetitive stimulation （10 V, 1 ms,20 Hz,4 s）of hypogastric nerves （HN） elicited a burst of action potentials which was followed by ls- EPSP in 61.1% （33/54） of the IMG neurons. The amplitude and duration of ls-EPSP were （7.7 ± 1.8）mV and （97.4 ± 17.4 ）s（ n = 33 ）, respectively. Superfusion of IMG with TFG evoked a concentration-dependent depression on the amplitude and duration of ls-EPSP in 69.7% of the neurons and 21.2% had no response to TFG. The depression induced by TFG was not blocked by cholinoceptor and adrenoceptor antagonists, but was eliminated in a low Ca^2＋/high Mg^2＋ Krebs solution. The depression induced by TFG could be enhanced by low Na^＋ （58 mmol/L） or high K^＋ （20 mmol/L） Krebs solution. It was also enhanced by TTX （10 μmmol/L）and weaken by tetraethylammonium（TEA, 1 retool/L）. Conclusion The inhibition of TFG on ls-EPSP could be observed on most neurons of IMG of guinea pig and the mechanism probably is associated with the decreasing influx of Na^＋ and increasing outflow of K^＋ .

关 键 词：神经节 交感/药物作用 兴奋性突触后电位 豚鼠 

分 类 号：R338[医药卫生—人体生理学]