KINDLING-INDUCED POTENTIATION IN THE PIRIFORM CORTEX
KINDLING-INDUCED POTENTIATION IN THE PIRIFORM CORTEX
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DOI：
10.1016/0006-8993(91)90309-j
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发表时间：
1991-08-16
期刊：
影响因子：
2.9
通讯作者：
EVANS, C
中科院分区：
文献类型：
--
作者：
RACINE, RJ;MOORE, KA;EVANS, C
在足以诱发癫痫样后放电的强度下，对边缘结构的重复电刺激可导致癫痫样反应（点燃）强度的永久性增加。 脉冲刺激引起的场电位在点燃后的许多前脑通路中的幅度也会增加。 这种点燃诱导的增强效应在许多方面与非致癫痫刺激产生的“长时程增强”（LTP）效应相似。 然而，也存在一些有趣的差异。 例如，点燃诱导的增强作用可以远远超过 LTP。 在这些实验中，我们试图确定嗅球点燃后，通过嗅球刺激在梨状皮层中引起的反应增强的持续时间。 该系统之所以成为攻击目标，是因为嗅球和梨状皮层都是高度反应性的点燃部位。 此外，我们使用配对脉冲技术来监测该系统的促进和抑制。 研究发现，引火物会引起梨状场电位的增强，这种增强持续至少 3 个月（实验期间），几乎没有衰减。 点燃也导致配对脉冲促进的减少。 在一些动物中，净促进变为净抑制。 这些结果与点燃会增加梨状皮层反复抑制的解释是一致的。 然而，配对脉搏测量值在 3 个月的测试期内恢复到接近基线水平。
At intensities sufficient to induce epileptiform afterdischarges, repeated electrical stimulation of limbic structures can lead to the development of permanent increases in the strength of the epileptiform response (kindling). Field potentials evoked by pulse stimulation are also increased in amplitude in a number of forebrain pathways following kindling. This kindling-induced potentiation effect is similar in many respects to the 'long-term potentiation' (LTP) effect which is produced by non-epileptogenic stimulation. There are, however, some interesting differences. For example, kindling-induced potentiation can far outlast LTP. In these experiments, we attempted to determine the longevity of the kindling-induced potentiation of the response evoked in the piriform cortex by olfactory bulb stimulation, following olfactory bulb kindling. This system was targeted because both the olfactory bulb and the piriform cortex are highly reactive kindling sites. In addition, we used the paired pulse technique to monitor facilitation and inhibition in this system. Kindling was found to induce a potentiation in the piriform field potential that lasted for at least 3 months (the period of the experiment) with little or no decay. Kindling also produced a decrease in paired pulse facilitation. In some animals the net facilitation was changed to a net depression. These results are consistent with the interpretation that kindling produces an increase in recurrent inhibition in the piriform cortex. The paired pulse measures, however, returned to near baseline levels over the 3-month test period.