Abstract:

AIM: The balance of excitation and inhibition of neurons and neuronal network is very important to perform complete neuronal function. Damage or loss of inhibitory γ-aminobutyric acid (GABA)-ergic interneuron is associated with impaired inhibitory control of cortical pyramidal neurons, leading to hyperexcitability and epileptogenesis. Ectopic neurons in the basal ganglia are to be one of the pathological features of epileptogenesis. In the present study, we investigated distribution of interneuron subtypes between neocortex and caudate nucleus.
METHODS: We performed immunohistochemistry of GABA, glutamic acid decarboxylase (GAD), calretinin (CR), calbindin (CB), parvalbumin (PV) and neuropeptide. We used surgical materials of four focal cortical dysplasia (FCD) cases, having lesions of neocortex and caudate nucleus, and eight age-matched autopsy controls. RESULTS: The pathology showed three FCD IIa, containing dysmorphic neurons, and one FCD IIb, balloon cells. In the neocortex, the concentrations (each positive cell number/all cell numbers in the evaluated field) of GAD+, CR+ and CB+ cells were significantly lower in FCD than in controls. On the contrary, in the caudate nucleus those of CR+ and CB+ cells were significantly more in FCD than in controls.
CONCLUSION: The interneuron imbalance between the neocortex and basal ganglia may affect the epileptogenesis of FCD.

日本語要旨:

26歳の精神運動発達遅滞を呈する女性で、MECP2遺伝子変異(c 1196_1200delCCACC (p P399QfsX4))を同定し、Rett症候群と診断した。この患者は、退行が11歳と遅く、変動するジストニアを呈するなど、 Rett症候群としては非典型的な例であった。