目的:观察与记录脊髓背角与伤害性信息传入有关的神经元的电生理活动特征,为研究痛与痛调制提供电生理学指标。方法:用经皮电刺激诱发大鼠脊髓背角神经元放电,玻璃微电极作细胞外记录,观察与伤害性电刺激有关的神经元的放电活动并输入...目的:观察与记录脊髓背角与伤害性信息传入有关的神经元的电生理活动特征,为研究痛与痛调制提供电生理学指标。方法:用经皮电刺激诱发大鼠脊髓背角神经元放电,玻璃微电极作细胞外记录,观察与伤害性电刺激有关的神经元的放电活动并输入示波器及计算机处理。结果:用兴奋 C 纤维阈上强度的经皮电刺激在脊髓背角诱导出两种型式的放电——两串放电及长串放电。两串放电包括早串放电与晚串放电。晚串放电中的长晚串放电常表现出"wind up"现象。结论:晚串放电活动与伤害性信息传入密切相关,其放电频率可作为痛调制研究中下行抑制作用的痛指标。展开更多
Objective： To investigate the expression of P2X receptors on rat intracardiac and paratracheal ganglion neurons. Methods： For preparation of intracardiac neurons, hearts were excised, the atria were separated and th...Objective： To investigate the expression of P2X receptors on rat intracardiac and paratracheal ganglion neurons. Methods： For preparation of intracardiac neurons, hearts were excised, the atria were separated and the medial region containing intracardiac ganglia was isolated and cut into pieces. For preparation of paratracheal neurons, the tracheas were removed and the superficial membranous layer containing paratracheal ganglia was rapidly isolated. Intracardiac and paratracheal ganglion neurons were dissociated after digestion by collagenase and trypsin. Whole-cell patch clamp recording was used to identify the pharmacological properties of P2X receptors in cultured neurons. Results：Neurons from these two ganglia responded to ATP with a rapidly activating, sustained inward current, αβ-meATP failed to evoke any re- sponses in paratracheal ganglion neurons while a few of intracardiac ganglion neurons responded to αβ- meATP with a tiny sustained inward current. ADP and UTP had no effect on intracardiac neurons. Lowering pH potentiated ATP responses in neurons from these two ganglia whereas increasing pH inhibited ATP responses. Co-application of Zn^2＋ potentiated ATP responses in intracardiac and paratracheal ganglion neurons. Conclusion： The receptor subtypes involved in intracardiac and paratracheal ganglia appear to be homomeric P2X2, while heteromeric P2X2/3 could not be completely excluded from intracardiac neurons.展开更多
Objective:To investigate the neural electrophysiologieal activity underlying Chinese and Eng- lish Stroop tasks for Chinese English bilinguals.Methods:Event-related potentials(ERPs)were recorded in 14 Chinese bilingua...Objective:To investigate the neural electrophysiologieal activity underlying Chinese and Eng- lish Stroop tasks for Chinese English bilinguals.Methods:Event-related potentials(ERPs)were recorded in 14 Chinese bilinguals with a moderate command of English when they performed the Stroop task pre- sented in English words and Chinese characters,respectively.Results:In Chinese task version,it was found an increased positivity over bilateral front-polar regions on incongruent trials compared with congru- ent trials,followed by an increased negativity over fronto-central region and an increased positivity over occipital region.While in English task version,only the increased negativity was observed over fronto-cen- tral region,but with reduced amplitude and anterior distribution.Conclusion:This increased negativity was proposed as an index of the resolution processes of conflicting information in the incongruent situa- tion.The increased positivity over occipital region on Chinese incongruent trials may indicate visually rechecking effect for Chinese character.展开更多
Objective. To investigate the properties of voltage-gated sodium (Na+) channels in developing auditoryneurons during early postnatal stages in the mammalian central nervous system.Methods. Using the whole-cell voltage...Objective. To investigate the properties of voltage-gated sodium (Na+) channels in developing auditoryneurons during early postnatal stages in the mammalian central nervous system.Methods. Using the whole-cell voltage-clamp technique, we have studied changes in the electrophysi-ological properties of Na+ channels in the principal neurons of the medial nucleus of the trapezoid body (MNTB).Results. We found that MNTB neurons already express functional Na+ channels at postnatal day 1 (P1),and that channel density begins to increase at P5 when the neurons receive synaptic innervation andreach its maximum (～3 fold) at P11 when functional hearing onsets. These changes were paralleled byan age-dependent acceleration in both inactivation and recovery from inactivation. In contrast, there wasvery little alteration in the voltage-dependence of inactivation.Conclusion. These profound changes in the properties of voltage-gated Na+ channels may increase theexcitability of MNTB neurons and enhance their phase-locking fidelity and capacity during high-frequencysynaptic transmission.展开更多
文摘目的:观察与记录脊髓背角与伤害性信息传入有关的神经元的电生理活动特征,为研究痛与痛调制提供电生理学指标。方法:用经皮电刺激诱发大鼠脊髓背角神经元放电,玻璃微电极作细胞外记录,观察与伤害性电刺激有关的神经元的放电活动并输入示波器及计算机处理。结果:用兴奋 C 纤维阈上强度的经皮电刺激在脊髓背角诱导出两种型式的放电——两串放电及长串放电。两串放电包括早串放电与晚串放电。晚串放电中的长晚串放电常表现出"wind up"现象。结论:晚串放电活动与伤害性信息传入密切相关,其放电频率可作为痛调制研究中下行抑制作用的痛指标。
基金Supported by the National Natural Foundation of China (No. 30570597)
文摘Objective： To investigate the expression of P2X receptors on rat intracardiac and paratracheal ganglion neurons. Methods： For preparation of intracardiac neurons, hearts were excised, the atria were separated and the medial region containing intracardiac ganglia was isolated and cut into pieces. For preparation of paratracheal neurons, the tracheas were removed and the superficial membranous layer containing paratracheal ganglia was rapidly isolated. Intracardiac and paratracheal ganglion neurons were dissociated after digestion by collagenase and trypsin. Whole-cell patch clamp recording was used to identify the pharmacological properties of P2X receptors in cultured neurons. Results：Neurons from these two ganglia responded to ATP with a rapidly activating, sustained inward current, αβ-meATP failed to evoke any re- sponses in paratracheal ganglion neurons while a few of intracardiac ganglion neurons responded to αβ- meATP with a tiny sustained inward current. ADP and UTP had no effect on intracardiac neurons. Lowering pH potentiated ATP responses in neurons from these two ganglia whereas increasing pH inhibited ATP responses. Co-application of Zn^2＋ potentiated ATP responses in intracardiac and paratracheal ganglion neurons. Conclusion： The receptor subtypes involved in intracardiac and paratracheal ganglia appear to be homomeric P2X2, while heteromeric P2X2/3 could not be completely excluded from intracardiac neurons.
文摘Objective:To investigate the neural electrophysiologieal activity underlying Chinese and Eng- lish Stroop tasks for Chinese English bilinguals.Methods:Event-related potentials(ERPs)were recorded in 14 Chinese bilinguals with a moderate command of English when they performed the Stroop task pre- sented in English words and Chinese characters,respectively.Results:In Chinese task version,it was found an increased positivity over bilateral front-polar regions on incongruent trials compared with congru- ent trials,followed by an increased negativity over fronto-central region and an increased positivity over occipital region.While in English task version,only the increased negativity was observed over fronto-cen- tral region,but with reduced amplitude and anterior distribution.Conclusion:This increased negativity was proposed as an index of the resolution processes of conflicting information in the incongruent situa- tion.The increased positivity over occipital region on Chinese incongruent trials may indicate visually rechecking effect for Chinese character.
基金This work was supported by an operaing grant and a scholarship from the Medical Research Council of Canada(MRC)and by a start-up fund from the Hospital for Sick Children Research Institute to L,Y.W.
文摘Objective. To investigate the properties of voltage-gated sodium (Na+) channels in developing auditoryneurons during early postnatal stages in the mammalian central nervous system.Methods. Using the whole-cell voltage-clamp technique, we have studied changes in the electrophysi-ological properties of Na+ channels in the principal neurons of the medial nucleus of the trapezoid body (MNTB).Results. We found that MNTB neurons already express functional Na+ channels at postnatal day 1 (P1),and that channel density begins to increase at P5 when the neurons receive synaptic innervation andreach its maximum (～3 fold) at P11 when functional hearing onsets. These changes were paralleled byan age-dependent acceleration in both inactivation and recovery from inactivation. In contrast, there wasvery little alteration in the voltage-dependence of inactivation.Conclusion. These profound changes in the properties of voltage-gated Na+ channels may increase theexcitability of MNTB neurons and enhance their phase-locking fidelity and capacity during high-frequencysynaptic transmission.
