title: Kindling-associated SV2A expression in hilar GABAergic interneurons of the mouse dentate gyrus.
abstract: Immunohistochemical studies were performed to analyze the expressional changes in hippocampal synaptic vesicle protein 2A (SV2A) following pentylenetetrazole (PTZ) kindling. Repeated treatments of mice with sub-convulsive PTZ (40 mg/kg, i.p.) for 15 days progressively enhanced seizure susceptibility and induced clonic convulsions in most animals examined. Topographical analysis of hippocampal SV2A-immunoreactivity revealed that SV2A was densely expressed in the hilar region of the dentate gyrus, stratum lucidum of the CA3 field and around the periphery of CA3 pyramidal neurons. PTZ kindling region-specifically increased SV2A expression in the dentate hilus without affecting that in the stratum lucidum or the pyramidal cell layer of the CA3 field. Confocal laser microscopic analysis using PTZ-kindled mice illustrated that most SV2A was co-expressed with glutamic acid decarboxylase 67 in the cell bodies and dendrites of hilar interneurons. However, SV2A-immunoreactivity was negligibly observed in the hilar glutamatergic nerve terminals (mossy fibers) probed with the anti-vesicular glutamate transporter 1 antibody. The present study suggests that SV2A specifically regulates hilar GABAergic neurotransmission in the kindled hippocampus probably as a compensatory or prophylactic mechanism against kindling epileptogenesis.
authors.affiliation: Laboratory of Pharmacology, Osaka University of Pharmaceutical Sciences, 4-20-1 Nasahara, Takatsuki, Osaka 569-1094, Japan. yohno@gly.oups.ac.jp
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Ohno
authors.forename: Takahiro
authors.initials: T
authors.lastname: Okumura
authors.forename: Ryo
authors.initials: R
authors.lastname: Terada
authors.forename: Shizuka
authors.initials: S
authors.lastname: Ishihara
authors.forename: Tadao
authors.initials: T
authors.lastname: Serikawa
authors.forename: Masashi
authors.initials: M
authors.lastname: Sasa
mesh_terms: D000818:Animals; D056547:CA1 Region, Hippocampal / Q000378:metabolism; D056654:CA3 Region, Hippocampal / Q000378:metabolism; D018891:Dentate Gyrus / Q000166:cytology / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D059330:GABAergic Neurons / Q000378:metabolism*; D007395:Interneurons / Q000378:metabolism*; D007696:Kindling, Neurologic; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism*; D051379:Mice; D018613:Microscopy, Confocal; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D010433:Pentylenetetrazole; D017966:Pyramidal Cells / Q000378:metabolism; D009435:Synaptic Transmission; D050598:Vesicular Glutamate Transport Protein 1 / Q000378:metabolism
chemical_list: D008562:Membrane Glycoproteins; D009419:Nerve Tissue Proteins; C493465:Slc17a7 protein, mouse; C489614:Sv2a protein, mouse; D050598:Vesicular Glutamate Transport Protein 1; D010433:Pentylenetetrazole