Electroencephalographic, behavioral, and c-fos responses to acute domoic acid exposure.
Neurotoxicol Teratol
; 26(2): 331-42, 2004.
Article
en En
| MEDLINE
| ID: mdl-15019966
ABSTRACT
Domoic acid, a potent excitotoxic analogue of glutamate and kainate, may cause seizures, amnesia, and sometimes death in humans consuming contaminated shellfish. Continuous behavioral observations and recordings of the electrocorticogram (ECoG, via bipolar, epidural electrodes) were obtained from nonanesthetized rats for 2 h after intraperitoneal injection with either saline, 2.2, or 4.4 mg/kg of domoic acid. Rats were then sacrificed for c-fos immunohistochemistry. Fast Fourier transformation (FFT) of the ECoG data to obtain the voltage as a function of frequency indicated that the lower frequency bands (theta, 4.75-6.75 Hz and delta, 1.25-4.50 Hz) were the first to respond, with a significant elevation by 30 min after the high dose of domoic acid. The lower dose of domoic acid also caused a significant elevation of ECoG voltage, but not until later in the session. Sixty minutes after dosing, the behavioral biomarkers of "ear scratching" and "rearing, praying" (RP) seizures became significantly elevated in the high-dose rats. The low-dose rats showed no significant alterations in behavior at any time during the session. In postmortem brains obtained immediately after the sessions, c-fos was activated in the anterior olfactory nucleus by both the low and high doses of domoic acid. However, only the high dose increased c-fos immunoreactivity in the hippocampus, affecting both the granule and pyramidal neurons. These data indicate that electroencephalographic and c-fos responses can be obtained at a dose of domoic acid that fails to activate the behavioral response most commonly used as a bioassay for this marine toxin ear scratching with the ipsilateral foot.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Conducta Animal
/
Proteínas Proto-Oncogénicas c-fos
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Electroencefalografía
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Ácido Kaínico
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Fármacos Neuromusculares Despolarizantes
Límite:
Animals
Idioma:
En
Revista:
Neurotoxicol Teratol
Asunto de la revista:
NEUROLOGIA
/
TOXICOLOGIA
Año:
2004
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
EEUU
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ESTADOS UNIDOS
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ESTADOS UNIDOS DA AMERICA
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EUA
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UNITED STATES
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UNITED STATES OF AMERICA
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US
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USA