Louvel J, Heinemann U
Electroencephalogr Clin Neurophysiol. 1983 Nov;56(5):457-66. doi: 10.1016/0013-4694(83)90229-8.
Effects of the convulsant drug oenanthotoxin on field potentials, neuronal discharges and extracellular free Ca2+ and K+ concentrations were studied in the sensorimotor cortex of cats. Fifteen to 20 min after topical OETX application spike activity developed (surface negative, deeper layers positive) with a frequency of 0.5-1/sec. With the maturation of the focus spikes became multipeaked and the reversal point of field potential polarity shifted deeper into the cortex. Spontaneous seizures developed when the spike activity had become negative in polarity in recording depths of 1300 micron below the cortical surface. Spontaneous seizures were associated with large rises in [K+]0 and reductions in [Ca2+]0 (delta [K+]0, delta [Ca]0). The latter were often larger than maximum changes in normal cortex. The decay in [Ca2+]0 associated with spontaneous seizures tended to precede the onset of ictal activity. The findings suggest that OETX, like other epileptogenic drugs, uses Ca2+-dependent mechanisms for the initiation of epileptiform activity.
在猫的感觉运动皮层中，研究了惊厥药物酒石酸毒素对场电位、神经元放电以及细胞外游离钙离子（Ca2+）和钾离子（K+）浓度的影响。局部应用酒石酸毒素15至20分钟后，出现了棘波活动（表面为负，深层为正），频率为0.5 - 1次/秒。随着病灶的成熟，棘波变得多峰，场电位极性的反转点向皮层更深层移动。当在皮层表面以下1300微米的记录深度处棘波活动的极性变为负时，出现了自发性癫痫发作。自发性癫痫发作与细胞外钾离子浓度（[K+]0）大幅升高和细胞外钙离子浓度（[Ca2+]0）降低有关（Δ[K+]0，Δ[Ca]0）。后者往往大于正常皮层中的最大变化。与自发性癫痫发作相关的[Ca2+]0衰减往往先于发作活动的开始。研究结果表明，酒石酸毒素与其他致癫痫药物一样，利用钙离子依赖机制引发癫痫样活动。
