LONG-LASTING POTENTIATION OF SYNAPTIC TRANSMISSION IN DENTATE AREA OF ANESTHETIZED RABBIT FOLLOWING STIMULATION OF PERFORANT PATH
LONG-LASTING POTENTIATION OF SYNAPTIC TRANSMISSION IN DENTATE AREA OF ANESTHETIZED RABBIT FOLLOWING STIMULATION OF PERFORANT PATH
复制标题
DOI：
10.1113/jphysiol.1973.sp010273
复制
发表时间：
1973-01-01
影响因子：
5.5
通讯作者：
LOMO, T
中科院分区：
文献类型：
--
作者：
BLISS, TVP;LOMO, T
1.用细胞外微电极检查了重复刺激海马结构齿状区的穿通路径纤维的后效应。在15/18只兔子中，在一次或多次以10-20/sec持续10-15 sec或100/sec持续3-4 sec的条件训练后，从齿状区颗粒细胞记录到的对单穿支通路齐射的群体反应增强了30 min至10 h。根据三个参数分析群体反应：群体兴奋性突触后电位（e. p. s. p.）的振幅，发出颗粒细胞去极化的信号，以及发出颗粒细胞放电信号的群体尖峰的幅度和潜伏期。所有这三个参数在29%的实验中增强;在发生长期变化的其他实验中，增强仅限于三个参数中的一个或两个。群体尖峰潜伏期的减少是最常见的增强迹象，发生在所有实验的57%。在所有实验中，群体eps的幅度增加了43%，群体峰的幅度增加了40%。在10-20/秒的条件反射过程中，群体尖峰（“频率增强”）有很大的增强作用。在100/sec的刺激过程中，尖峰被抑制。两种频率都产生长时程增强。结果表明，两个独立的机制是负责持久的增强：（a）在穿孔路径突触的突触传递效率的增加;（B）在颗粒细胞群的兴奋性增加。
1. The after‐effects of repetitive stimulation of the perforant path fibres to the dentate area of the hippocampal formation have been examined with extracellular micro‐electrodes in rabbits anaesthetized with urethane.2. In fifteen out of eighteen rabbits the population response recorded from granule cells in the dentate area to single perforant path volleys was potentiated for periods ranging from 30 min to 10 hr after one or more conditioning trains at 10–20/sec for 10–15 sec, or 100/sec for 3–4 sec.3. The population response was analysed in terms of three parameters: the amplitude of the population excitatory post‐synaptic potential (e.p.s.p.), signalling the depolarization of the granule cells, and the amplitude and latency of the population spike, signalling the discharge of the granule cells.4. All three parameters were potentiated in 29% of the experiments; in other experiments in which long term changes occurred, potentiation was confined to one or two of the three parameters. A reduction in the latency of the population spike was the commonest sign of potentiation, occurring in 57% of all experiments. The amplitude of the population e.p.s.p. was increased in 43%, and of the population spike in 40%, of all experiments.5. During conditioning at 10–20/sec there was massive potentiation of the population spike (‘frequency potentiation’). The spike was suppressed during stimulation at 100/sec. Both frequencies produced long‐term potentiation.6. The results suggest that two independent mechanisms are responsible for long‐lasting potentiation: (a) an increase in the efficiency of synaptic transmission at the perforant path synapses; (b) an increase in the excitability of the granule cell population.