Chelation of synaptic zinc induces overexcitation in the hilar mossy cells of the rat hippocampus.
Complete removal of synaptic zinc by the chelator dietyldithiocarbamate (DEDTC; 500 mg/kg i.p.) in rat was followed by convulsive behaviour including wet dog shakes alternating immobility. Histological analysis 1 day after DEDTC administration detected expression of heat shock protein in the hippocampus restricted to hilar cells. These cells colocalize the marker for neurons and the glutamate receptor GluR2/3 showing that they are excitatory neurons. Additionally, they projected to the contralateral dentate gyrus. Therefore, they correspond to hilar mossy cells. These data show that the synaptic zinc has a role in normal hippocampus avoiding overexcitation, that would impair functionality even in absence of pathological or exoexcitotoxic phenomena.
Blasco-Ibáñez
José-Miguel
JM
Departamento de Biología Celular, Unidad de Neurobiología, Facultad de Ciencias Biológicas, Universidad de Valencia, Str. Dr Moliner 50, E-46.100 Burjasot, Spain. jose.m.blasco@uv.es
Poza-Aznar
Julio
J
Crespo
Carlos
C
Marqués-Marí
Ana-Isabel
AI
Gracia-Llanes
Francisco-Javier
FJ
Martínez-Guijarro
Francisco-José
FJ
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D002614:Chelating Agents / Q000494:pharmacology; D018891:Dentate Gyrus / Q000187:drug effects / Q000378:metabolism*; D004050:Ditiocarb / Q000031:analogs & derivatives* / Q000494:pharmacology; D050884:HSP72 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000187:drug effects / Q000378:metabolism; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D007150:Immunohistochemistry; D019599:Mossy Fibers, Hippocampal / Q000187:drug effects / Q000378:metabolism*; D009434:Neural Pathways / Q000187:drug effects / Q000378:metabolism*; D017729:Presynaptic Terminals / Q000187:drug effects / Q000378:metabolism*; D016760:Proto-Oncogene Proteins c-fos / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D018091:Receptors, AMPA / Q000378:metabolism; D012640:Seizures / Q000139:chemically induced / Q000378:metabolism / Q000503:physiopathology; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology*; D018998:Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate; D015032:Zinc / Q000172:deficiency* / Q000378:metabolism
D002614:Chelating Agents; D050884:HSP72 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D016760:Proto-Oncogene Proteins c-fos; D018091:Receptors, AMPA; D018998:Wheat Germ Agglutinin-Horseradish Peroxidase Conjugate; C062844:wheat germ agglutinin-apohorseradish peroxidase conjugate gold complex; D004050:Ditiocarb; C039353:dihydroxyethyldithiocarbamate; D015032:Zinc; C104722:glutamate receptor ionotropic, AMPA 2