Silva-Barrat C, Brailowsky S, Riche D, Menini C
Laboratoire de Physiologie Nerveuse, CNRS, Gif-sur-Yvette, France.
Exp Neurol. 1988 Sep;101(3):418-27. doi: 10.1016/0014-4886(88)90053-2.
We studied the effects of chronic (7 day) infusions of GABA (100 and 20 micrograms/microliter, 10 microliter/h) applied in different cerebral structures of baboons made photosensitive by a subconvulsant dose of allylglycine. The GABA infusion has partial anticonvulsant effects when applied to the motor cortex, reticular magnocellular nucleus (RMC), or substantia nigra (SN), but when directed to the prefrontal cortex (area 8) it has no effect. These anticonvulsant effects of GABA infusion are more important when GABA is infused into the motor cortex, where paroxysmal discharges (PDs) originate, than when it is infused into the RMC. In contrast, the anticonvulsant effects on light-induced generalized seizures are more pronounced when GABA is infused into the RMC than when it is infused into the motor cortex. GABA infusion into the SN has no effect on PDs and myoclonia and blocks seizures less effectively than the RMC infusion. These results are in accordance with the role of the motor cortex as a generator of PDs and of RMC in the generalization of seizures. Focal paroxysmal EEG and clinical activities, previously reported to appear at the end of the motor cortex GABA infusion, were not observed after RMC or SN infusions. However, behavioral hyperactivity occurring at the end of subcortical GABA infusions was observed. These behavioral signs could correspond to the clinical expression of a GABA withdrawal syndrome.
我们研究了在经亚惊厥剂量烯丙基甘氨酸致敏而变得光敏的狒狒的不同脑结构中，慢性（7天）输注γ-氨基丁酸（GABA，100和20微克/微升，10微升/小时）的影响。当将GABA输注应用于运动皮层、巨细胞网状核（RMC）或黑质（SN）时，具有部分抗惊厥作用，但当针对前额叶皮层（8区）时则无作用。当将GABA输注到运动皮层（阵发性放电（PDs）起源于此）时，其抗惊厥作用比输注到RMC时更重要。相反，当将GABA输注到RMC时，对光诱导的全身性惊厥的抗惊厥作用比输注到运动皮层时更明显。将GABA输注到SN对PDs和肌阵挛无作用，且其阻断惊厥的效果不如输注到RMC有效。这些结果与运动皮层作为PDs的起源部位以及RMC在惊厥泛化中的作用相符。先前报道在运动皮层GABA输注结束时出现的局灶性阵发性脑电图和临床活动，在RMC或SN输注后未观察到。然而，在皮层下GABA输注结束时出现了行为多动。这些行为体征可能对应于GABA戒断综合征的临床表型。
