Mattia D, Hwa G G, Avoli M
Montreal Neurological Institute, Qué., Canada.
Neurosci Lett. 1993 May 14;154(1-2):157-60. doi: 10.1016/0304-3940(93)90195-q.
Extracellular field recordings were performed in guinea-pig and rat neocortical slice preparations maintained in vitro. Bath application of the convulsant drug 4-aminopyridine (4-AP, 100 microM) induced spontaneous epileptiform potentials in 80% of the guinea-pig neocortical slices and only in 6% of the neocortical slices from rat. In both species spontaneous epileptiform activity consisted of a 4-16 s long ictal-like discharge that recurred with a frequency range of 0.01-0.02 Hz. In rat neocortical slices stimulus-induced responses resembled the spontaneous occurring epileptiform events. Ictal-like discharges in guinea-pig neocortical slices were blocked by the N-methyl-D-aspartate (NMDA) receptor antagonist 3-((+/-)-2-carboxypiperazine-4-yl)propyl-1-phosphonic acid (5 microM), while those in the rat disappeared during perfusion with the non-NMDA excitatory amino acid receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (1-3 microM). These results indicate that the neocortex of guinea-pig has a higher propensity to generate 4-AP-induced spontaneous epileptiform activity than that of rat. Furthermore the epileptiform activity in these two species requires a different involvement of excitatory amino acid receptors.
在体外维持的豚鼠和大鼠新皮质脑片标本上进行了细胞外场记录。向浴槽中加入惊厥药物4-氨基吡啶（4-AP，100微摩尔）后，80%的豚鼠新皮质脑片诱发出自发癫痫样电位，而大鼠新皮质脑片中只有6%出现这种情况。在这两个物种中，自发癫痫样活动均表现为持续4 - 16秒的发作样放电，其复发频率范围为0.01 - 0.02赫兹。在大鼠新皮质脑片中，刺激诱发的反应类似于自发出现的癫痫样事件。豚鼠新皮质脑片中的发作样放电被N-甲基-D-天冬氨酸（NMDA）受体拮抗剂3-((±)-2-羧基哌嗪-4-基)丙基-1-膦酸（5微摩尔）阻断，而在灌注非NMDA兴奋性氨基酸受体拮抗剂6-氰基-7-硝基喹喔啉-2,3-二酮（1 - 3微摩尔）期间，大鼠脑片中的发作样放电消失。这些结果表明，豚鼠新皮质比大鼠新皮质更易产生4-AP诱导的自发癫痫样活动。此外，这两个物种中的癫痫样活动需要不同的兴奋性氨基酸受体参与。
