Pan Bin, Yang Dong-Wei, Han Tai-Zhen, Xie Wen
Department of Physiology, School of Medicine, Xi'an Jiaotong University, Zhuque Dajie 205, Xi'an, Shaanxi 710061, PR China.
Brain Res. 2004 Sep 17;1021(1):146-50. doi: 10.1016/j.brainres.2004.06.046.
The effects of 2- and 100-Hz tetanus on long-term potentiation (LTP) of field potentials recorded from layers II/III and induced in layer IV in rat visual cortical slices were examined. Paired-pulse stimulation was used to probe the different mechanisms of LTP induced by 2- and 100-Hz tetanus. The paired-pulse ratio (PPR) decreased after the LTP induced by 2-Hz tetanus, with the changes in PPR being correlated with LTP amplitude. However, in the LTP induced by 100-Hz tetanus, the changes in PPR were not correlated with LTP expression. These experiments suggest that an enhanced probability of presynaptic transmitter release underlies LTP induced by 2-Hz tetanus, but not LTP induced by 100-Hz tetanus.
研究了2赫兹和100赫兹强直刺激对大鼠视觉皮层切片II/III层记录到的、IV层诱导产生的场电位长时程增强（LTP）的影响。采用双脉冲刺激来探究2赫兹和100赫兹强直刺激诱导产生LTP的不同机制。2赫兹强直刺激诱导产生LTP后，双脉冲比率（PPR）降低，PPR的变化与LTP幅度相关。然而，在100赫兹强直刺激诱导产生的LTP中，PPR的变化与LTP表达不相关。这些实验表明，2赫兹强直刺激诱导产生的LTP的基础是突触前递质释放概率增加，而100赫兹强直刺激诱导产生的LTP并非如此。
